Author's Note

Limestone had the most votes (only one vote this time around named anypony else), so she's the star of this chapter.

Inspiration once again comes from Scootabom1, who proposed that Limestone be regressed, have a lisp, and be grabby. And he proposed somepony being disciplined, but leaving it up to me whether or not Twilight would also be disciplined. He did suggest Marble Pie also be present and not be regressed, but he is the only one who mentioned Marble Pie when voting for Limestone. And before that, Limestone and Marble had been mentioned together only once, indirectly. Lastly, he suggested that Limestone apologize when the regression wore off.

As a result, this chapter will contain disciplinary spanking in addition to the usual fetish content. Again, it is not meant to be sexual, the sex tag is there solely as a precaution because it was in the original fic. In a way, this chapter is a lot like the Rainbow Dash chapter from the original fic, which also contained spanking (among other things).

Voting is back to its regular schedule of a month from when the chapter is published. I will inform you if the date changes.

Characters that can only be done in group pairings:
Mane six
Princess Cadence
Princess Luna
Octavia and Vinyl Scratch
Twilight Velvet
Spitfire (with or without Wonderbolts)
Lightning Dust
Maud Pie (without Mudbriar)
Moondancer
Cheerilee
Lyra and Bon Bon (separately, or together)
Coco
Limestone Pie

Characters that can only be done in specific group pairings:
Spike (with mane six, Princess Cadence, or Sparkle family)
Shining Armor (with Princess Cadence, or Sparkle Family

Characters previously voted on:
Derpy, Marble Pie - One vote
Sassy Saddles, Fleur, Princess Celestia - One half vote

Limey (Limestone Pie)

Twilight was a little bit surprised when she woke up one morning in her bedroom, and found that Princess Celestia was nowhere to be seen. Twilight was still in her diapers, so it wasn't like her fellow alicorn to just leave her unattended. Something had to be up.

Feeling a tad bit scared and concerned, Twilight nevertheless threw back the covers of her bed, sat up, and climbed out. Hopefully, whatever it was that was keeping Princess Celestia preoccupied would resolve itself soon. Twilight couldn't wait to spend time with her "mommy" again. She didn't think there was anything wrong with that, it was just a role she was playing, one that her fellow alicorn was happy to support and encourage. As long as it stayed between them and ponies in the know, that was fine. Besides, since when was there a rule or a law that said princesses couldn't wear diapers?

The padded princess waited, and waited, and waited some more. She waited as patiently as possible under the circumstances. Yet even though time passed, there was still no sign of the sun princess, and no indications as to her whereabouts. Twilight naturally began to worry, levitating Smarty Pants over and talking to the old doll. "Smarty Pants, do you think Mommy is okay? She's never been this late before."

"I don't know, Twily," Smarty Pants replied in a somewhat anxious tone. "Maybe she overslept? Or maybe she's in the little filly's room using the potty?"

"Nah, that can't be it," Twilight protested. "Besides, there's a potty right here in my bedroom. Mommy could just use that, and that way I'd know where she was," She began to whimper ever so faintly. "What if Mommy's forgotten about me? She's been so busy lately."

Smarty Pants tried to reassure the padded princess. "Twily, that's ridiculous. Mommy could never forget about you. I've seen it with my own eyes the bond you share with her."

Whimpering softly and fighting back tears, the diaper wearing alicorn questioned aloud. "Then where is she, Smarty Pants? I want to go look for her. But I don't want everypony in the castle to see me wearing diapers, they'll all make fun of me for sure. They'll start spreading rumors about me. My whole life will be ruined!"

Fortunately, it was at that very moment that Princess Celestia finally appeared. Upon seeing the concerned look on Twilight's face, she unfolded her wings and trotted forward, draping them over her fellow alicorn as she spoke softly and sweetly. "It's okay, Twily. I'm here now. Mommy is sorry if she made you worry. She didn't mean to."

"That's okay, Mommy," Twilight replied as she leaned fully into the wing hug. "I know you must've been busy. I'm just glad you're not hurt or lost or anything like that," She then proudly presented her diaper. "And look, Mommy! I'm still clean! I haven't gone pee-pee or poo-poo yet! Isn't that great?!"

The sun princess smiled and nodded, showering Twilight with only slightly exaggerated praise. "Yes that is, Twily! I'm proud of you for putting so much effort into that! But you know that I will still love you even if you use your diapers for number one and number two. I will always love you no matter what, Twily. That's what a mommy is for."

"Hey, don't forget about me, Mommy!" Smarty Pants spoke up. "I've been with Twily too. Wherever she goes, I go."

Princess Celestia chuckled ever so faintly. "Of course I haven't forgotten about you, Smarty Pants. You're there for Twily even when I can't be. I will always be grateful for that."

Twilight then asked. "So, what took you so long, Mommy?" With a concerned look on her face and a concerned tone in her voice, she reluctantly inquired. "Is something wrong in Equestria? Is it some important event that needed planning or scheduling?"

The alicorn with a majestic white coat shook her head from side to side. "Oh no, it's nothing like that, Twily. If it was, I would make sure you knew about it," She turned her attention back to the bedroom door. "It's just that..." She hesitated, apparently trying to think about how best to frame what she was going to say next. After a moment or so of silent contemplation, she continued. "-Your next playmate proved to be more difficult than I had anticipated." And as soon as she finished saying those words, she lit up her horn and opened the bedroom door, quickly ushering in the aforementioned playmate.

It was an earth pony mare with a bluish gray coat, opalish gray mane and tail that hung flat against her sides, moderate amber eyes that seemed to have a far away look in them, and a cutie mark depicting a lime between two rocks that was faintly visible through the diaper she was wearing. "Hi, Twiwy." The mare spoke, lisping slightly in a tone of voice that still sounded gruff. It was possible to see a faint bit of drool escaping her lips.

Princess Celestia explained. "Twily, this is Limestone Pie. But you can call her Limey. As you can clearly see, she's been regressed to the mindset of a foal. I had to do it rather heavily, because she was being very fussy and uncooperative about the whole experience. I hope that she won't be too much trouble for you."

"Of course not," Twilight insisted. "But why did you choose her, Mommy? Marble was the one who got put back into diapers, Limey was the one who teased her about it."

The sun princess struggled to suppress a goofy grin. "Precisely why I felt Limey here could benefit from spending some time with you. She most certainly could use a break from all her big pony responsibilities. They were putting so much stress on her."

Limestone made a face and stuck out her tongue. "Aww wowk, no pway. Mommy and Daddy no fun at aww."

The padded princess giggled. Just like when Rarity had been mentally regressed, she knew that this sort of infantile behavior from Limestone was something she would probably never see again. And from what Pinkie Pie had told her, Limestone could be very grumpy and very bossy. So perhaps a bit of time spent back in diapers and freed from all the burdens and responsibilities that came with being the eldest sibling would help.

Once satisfied that Twilight was onboard with her new playmate, Princess Celestia took the liberty of asking. "Alright, my little ponies. What would you like to do first today? I know nopony needs a diaper change, so we can rule that out for the time being."

As if in answer to the elder alicorn's question, both Twilight and Limestone heard their stomachs grumble and rumble quite audibly. Limestone even took the liberty of babbling. "Hungy. Feed me!" And she said in a noticeably demanding, impatient tone of voice. It seemed that her fussy attitude hadn't been completely taken away in spite of her mental regression.

"I'm hungry too, Mommy." Twilight spoke up in a considerably nicer tone.

The sun princess nodded. "Alright then, breakfast it is. Come with me, my little ponies, and we'll see what delicious num-nums are on the menu for today." Taking hold of her charges by the hoof, she lit up her horn and teleported them to the royal dining room, which was (of course) void of other ponies.

Twilight and Limestone were soon placed into chairs adjacent to one another, their padded rears crinkling audibly as they sat down. Smarty Pants sat off to Twilight's left, waiting patiently.

Princess Celestia was quick to tie bibs around the necks of both padded mares, then she disappeared into the kitchen for a moment or two. When she returned, she brought with her shiny plates piled high with sweet, savory pancakes. The aroma of them wafted through the air, making both Twilight and Limestone's mouths water. The pancakes themselves were topped with syrup, butter, and whipped cream, which made them look absolutely tasty and tempting.

As soon as the plates were set down, Limestone eagerly reached out a hoof to try to grab them. "Mine!" She shouted!

Celestia carefully repelled Limestone's grabby hooves with her magic. "Ah ah ah, Limey," She lightly scolded in a playful tone. "You have to wait for Mommy to cut up your pancakes first. That's how it works," And she turned to Twilight. "Twily, don't you get any ideas either. I know I taught you better than that."

"Uh-huh, Mommy. I'll be good." Twilight promised. To demonstrate this fact, she sat upright in her chair and did not move in the slightest. It was hard to do so, the pancakes looked so delicious. But the rules were the rules. She had to wait until they'd been cut up and offered to her.

The alicorn with a majestic white coat and a multi-colored mane then used her magic to cut up the pancakes on the plate, until they were reduced to small squares full of syrup, butter, and whipped cream. She then sat across from the padded ponies in her presence, carefully pushing the plates towards them whilst using her magic to hold up a plastic fork. "Open wide for the choo-choo train!" She cooed, presenting the first cut of pancakes to Twilight, perhaps in the hopes that she could get Limestone to see how the proper way a foal was to behave.

The younger alicorn obeyed the command and opened her mouth as wide as she could. She was rewarded for her efforts when the portion of pancake was deposited into her mouth. She started chewing once the fork was removed, delighting in the taste that nearly overwhelmed her taste buds. "Oh boy, chocolate chip! My favorite!" She exclaimed as her eyes went wide! "Thank you, Mommy!" She said in between bites.

Princess Celestia playfully chuckled. "Twily, don't talk with your mouth full."

"Sorry." Twilight apologized, turning a faint shade of pink in the process.

"Haha!" Limestone pointed and laughed, kicking all about. She seemed to find the scene hilarious.

"Hey, don't make fun of Twily! She couldn't help herself! Those pancakes were really good!" Smarty Pants protested to Limestone.

The regressed earth pony mare ignored the doll. She instead turned to her own plate of pancakes, the look and smell of them becoming more irresistible by the minute.

Sure enough, before Princess Celestia could turn and start feeding Limestone, Limestone started digging into the pancakes with her bare hooves. Crumbs flew everywhere as she smeared the syrup, butter, and whipped cream all over her face. She devoured pancake slice after pancake slice quite audibly, and without the slightest care for table manners. When she was finished, she leaned back in her chair, patted her stomach, and let an audible belch. "'Scuse me." Then she licked her lips, trying to get the traces of syrup, butter, and whipped cream that stuck to her cheeks.

"My goodness!" Celestia exclaimed in what sounded like only slightly exaggerated shock. "Just look at the mess you made, Limestone!" She summoned up a wet rag with her magic, and began using it to try to clean the earth pony's face. It was a task made difficult by the fact that Limestone didn't want to cooperate. Try as she might, the sun princess could only get a tiny bit of syrup, butter, and whipped cream removed. At last, with a frown, she turned back to Twilight and declared. "Once I've finished feeding Twily, I'm going to have to give you a bath, little Limey. I can't leave that stuff to get stuck on your face all day."

Limestone, for her part, just giggled. Her attention was focused on playing with her hooves and her padding. She seemed to find the whole thing amusing.

Fortunately for Twilight and Celestia, the padded alicorn was much more cooperative when it came to feeding. By the time her plate was empty, only a few small crumbs remained plastered on her face. And they were easily removed with a single wipe from a wet rag.

The now empty dishes were floated back into the kitchen to be cleaned out and put away, and then Princess Celestia gave her full attention to the still very messy earth pony in her presence. With a great deal of effort, she floated Limestone into the air and held her close. "Alright, Limey, let's get you cleaned up."

"Please, Mommy, can I have a bath too?" Twilight pleaded with puppy dog eyes.

The sun princess resisted the eyes and replied. "Maybe later, Twily. Right now, I need to get Limey all cleaned up before all that stuff sticks to her face. You're welcome to stay by my side and watch. You can even help me clean her up if you'd like."

But Twilight shook her head from side to side. "Nah, don't wanna."

Celestia just sighed. "Alright, then I don't wanna hear any complaining about how long it takes," She began to carry Limestone off. "I'm definitely going to have my work cut out for me," Trotting back to Twilight's bedroom, she said to her fellow alicorn. "Just stay here and don't run off. And if you need anything, Twily, let me know." Then she trotted into the bathroom, turned on the lights, and began filling up the tub with warm, soapy water.

Twilight waited and waited, pacing the floor and shuffling back and forth on her padded posture. She could hear the sound of running water from the bathtub, the sound of splashing hooves as Limestone was deposited into the tub and started making a fuss, and the sound of furious rubbing and scrubbing as Princess Celestia tried to get the regressed earth pony fully cleaned.

It seemed to take ages, the minutes ticking by in agnoizing slowness. Surely, Limestone hadn't made that much of a mess of herself, had she?

At last, the long wait was over. The padded alicorn's trained ears could pick the sound of water being drained, signaling that the bath for Limestone was ending. Yet it was then that she heard an audible "Pfft!", followed by giggles and a playful, mischievious voice saying. "Heh heh, I pooted."

A minute or so later, and Limestone emerged from the bathroom with a clean face and a spotless diaper. She still had that cheeky grin plastered on her face, apparently finding the whole thing amusing.

Princess Celestia, for her part, looked frazzled. And it really didn't seem to be an act. "Limey is being quite the hoofful today, it seems."

Twilight waddled up to her fellow alicorn, nuzzling her in the side. "It's okay, Mommy. You still have me, and Smarty Pants. We won't be naughty for you. Will we, Smarty Pants?"

"No we won't!" Smarty Pants firmly insisted. "We'll be the best little foals ever for you, Mommy!"

The alicorn mare with a majestic white coat smiled ever so faintly. Such affection and promise seemed to ease her nerves a bit. "That's good. I know you both mean it," Then she used her magic to pull Limestone close, all the while exposing her teets. "Now then, how's about some milk to wash down those pancakes? I have to make sure my foals are getting their nutrition."

Limestone wasted no time in latching on to the first teet she could lay eyes on! "Mine!" She shouted again, practically biting down on it in the process.

Celestia let out a yelp. "Careful, Limey! Not so hard! That's a very sensitive area."

Undeterred, the earth pony mare just started suckling. She was suckling so fast, it was a miracle she remembered to breathe. It was almost as if she viewed the whole thing as a competition, and was trying to hoard all the milk to herself.

The padded princess, for her part, suckled much more gently and much more slowly. She was confident that there was more than enough milk to go around. And she closed her eyes, concentrating on her fellow alicorn's steady heart beat while timing her suckles to the rhythm. It tasted just as sweet as it always did.

In a matter of minutes, both padded mares had their bellies filled to the brim with milk. And it was of great relief to them that they were floated up and patted on the back repeatedly by Princess Celestia afterwards. Twilight almost thought she was going to spit up from how full she was, but was greatly relieved when she just belched instead. The full feeling in her tummy slowly settled, allowing her to be set back down.

With the breast feeding complete, Princess Celestia plopped her posture down into a chair and brought a hoof up to her forehead. "I think I need to rest for a little bit," She told her charges. "You two just stay here and play nice. There's plenty of toys for you both." She promptly gestured a hoof to an oversized toy chest resting off in a corner of the bedroom.

Upon seeing the toychest, Limestone's eyes went wide with wonder! She immediately rushed for them at a speed that could've rivaled Pinkie Pie's or Rainbow Dash's! "Toys!" She exclaimed again and again!

Twilight trotted towards the toy chest as well, but at a much slower pace. As excited as she was at the prospect of playtime, she was still feeling a little full from the pancakes and the breast milk. There was no doubt about it, she had overindulged. But she couldn't help it, the pancakes and the milk had tasted so sweet. She hadn't wanted to stop, even after her stomach had tried to get her to do so.

That didn't deter the regressed earth pony mare with a bluish-gray coat. Perhaps she was used to eating bigger meals, or perhaps she just had a faster working digestive system. Whatever was the case, she all but dove into the toy chest, grabbing as many different toys as she could lay eyes on. "This mine! That mine too!" She lisped, holding every toy she grabbed close to her chest. "Tey aww mine!" One could easily have mistaken her for a greedy dragon building a hoard.

The padded princess simply took possession of whatever toys Limestone didn't want or couldn't get her hooves on. Luckily, there were still some alphabet blocks and a few plushies left at the bottom of the chest. It was better than nothing. Looking to Smarty Pants, she quickly got an idea. "Let's have a tea party!" She said to the old doll.

"What a great idea, Twily!" Smarty Pants eagerly replied. "A tea party's always better with more guests."

"Uh-huh. You're so smart, Smarty Pants!" Twilight cooed as she hugged the doll tightly.

Smarty Pants playfully giggled. "That's why they call me Smarty Pants, Twily. Now come on, help me get the table and chairs set up for our guests. They'll be here soon!"

The diaper wearing alicorn thus went about arranging the alphabet blocks in a small circle, spacing them apart so that they loosely resembled chairs. Once she placed the last block, she set all of the plushies down on top of them one by one, and then placed Smarty Pants on one of the two remaining blocks.

But as Twilight moved to sit down in her own chair, she felt it be suddenly yanked away from her by her fellow padded mare. "Mine!" Limestone shouted, sticking out her tongue and swishing her tail.

"Hey, give that back!" Twilight cried as she fell upon her padded posture, relieved that it had cushioned the impact.

The earth pony mare refused to obey, instead replying. "Nu-uh, tis mine! Ya can't have it!" And she held it high above her head, almost as if she were taunting the padded princess.

The alicorn princess thus complained. "You're being mean, Limey! Stop it!"

Limestone didn't seem to care in the slightest. "Not giving it back!" She lisped in protest and ran off with it, carrying it across the room to her huge pile of toys. She wasn't really playing with any of them, she just seemed to have wanted solely for the sake of having them.

"You already have enough toys! You're not being fair!" Twilight started to whimper. Playtime with Limestone was starting to not be very fun at all. Lighting up her horn, she tried to take one of the other toys from the pile, hoping to maybe use it as part of a trade or a negotiation.

The regressed earth pony mare refused to part with any of her toys. Whenever she saw one being taken away from her by magic, she lunged for it and grasped it firmly in her hooves, refusing to let it go. "Is mine! I no wanna shawe with you!" She protested with a growl, even briefly bearing her teeth. The regression had apparently made her possessiveness and clinginess even worse. Twilight was starting to feel bad for the other Pie sisters, all of whom surely had had to put up with such behavior on their rock farm.

Princess Celestia, meanwhile, could hear the arguing back and forth. And because she had been trying to rest and relax, the noise sounded that much louder than it otherwise might have been. Yet she didn't want to get up from the chair she was sitting in, she still felt exhausted. So instead, with a disapproving glare and a harsh frown, she spoke to the padded ponies. "Now now, my little ponies. Play nice. Don't make me separate you two."

"But Mommy, Limey's not sharing!" Twilight whined. "She's being a poopy head!"

"Nu-uh! Twily not weaving me awone!" Limestone complained. "She the poopy head!"

Celestia sighed deeply. "I don't care who's fault it is or who's doing what. You two need to learn how to share and get along," She then warned. "If I have to get up from this chair and come over there, there will be consequences. I'm not going to warn you again: Play nice, or you'll force me to take drastic measures."

At that the padded princess froze and her eyes shrank. Though faint, she could recall what had happened the last time she'd angered the sun princess to such a degree. She had been disciplined very harshly, her rump had been sore for almost an entire day afterwards. She dared not risk it happening again.

If Limestone was bothered by the threat, she didn't show it outwardly! She just laughed as she continued to guard her large pile of toys! "Mine! Aww mine! You can't have it!" She insisted with narrowed eyes. Then she happened to notice Smarty Pants resting on the ground near the other plushies. Immediately, she lunged for it and grabbed hold of the doll by one end.

Twilight wasn't about to let Smarty Pants go, not without a fight! Lighting up her horn, she grabbed Smarty Pants by the other end and tugged as hard as she could! "NO!" She screamed! "Smarty Pants isn't yours! You have enough toys already!"

"Want Smawty Pants! Give hew!" Limestone growled, biting down on the doll with her teeth and digging in her hooves.

With eyes narrowed and teeth gritted, the diaper wearing alicorn just increased her magical hold. She forgot all about anything else, let alone the fact that Smarty Pants was extremely delicate (Big Macintosh had done a pretty good job of sewing the old doll back up, but there were still seams that were very easily exposed with the right amount of tension). "No!" She protested.

And so the arguing went back and forth, the two padded ponies pulling on opposite ends of the old doll as they each tried to claim it only for themselves. All the while they shouted to each other "Give me!" and "No!" over and over again!

Suddenly, the argument was abruptly halted as a bright yellow glow took hold of Smarty Pants in her entirety and lifted her so high into the air that neither Twilight or Limestone could reach it. "That's quite enough, both of you!" A very stern, disapproving tone of voice rang out, echoing throughout the entire bedroom and filling both padded mares with a sense of dread. Now standing before them was the visibly irritated form of Princess Celestia, who did not seem amused in the slightest.

Twilight eeped, accusingly gesturing a hoof! "Mommy, it's not my fault! It's all Limey's fault!"

"Nu-uh, is Twiwy's fauwt!" Limestone protested, lacking any better argument.

Celestia just frowned and scowled. "I specifically warned you two what would happen if you didn't stop fighting. I asked you nicely to get along. And you disobeyed me. You're both at fault, and you're both going to be punished for this. You two should know better than to fight over a doll."

Even though she was certain she knew what was coming, the padded princess still hesitantly and nervously asked her fellow alicorn. "W-what's going to happen to us, Mommy? What are you gonna do?"

The alicorn mare with a majestic white coat sighed deeply even as her overall expression did not change. "What any mommy does when confronted with naughty foals who don't listen to her," She carefully floated Smarty Pants over to a huge shelf and turned the doll so that its back was showing to the foals. "I've made sure Smarty Pants can't see what's going to happen. Don't either of you try to run away from this. You must be punished. And then you're both going to sit in time out and think about what you did wrong."

Twilight shuddered with visible horror. She couldn't believe she was about to be disciplined again. "P-please, Mommy! I'm sorry! I won't do it again!" She pleaded.

Princess Celestia could only shake her head in disapproval. She would not be deterred or persuaded otherwise. "I'm sorry, Twily. Believe me, this hurts me as much as it's going to hurt you. But it has to be done. It's the only way I can make sure you'll learn your lesson," She promptly sat down on a stool, motioning first to Limestone. "You're first, Limey. You made this disturbance, so you are going to receive a harsher punishment."

"Ya not the boss of me!" Limestone stuck out her tongue in defiance and tried to run away! She couldn't get far, however. As strong as she might be, she was no match for Princess Celestia. Wiggling, squirming, and kicking in protest, she was brought before the princess and had her diaper pulled down, exposing her bare bottom.

"Turn around please, Twily." Celestia instructed. And she waited until her fellow princess had obeyed before carrying out the punishing of Limestone. She swiftly brought her hoof down upon the earth pony's rump, smacking it hard! Then she did it again, and again, and again. Swat after swat followed, causing Limestone's rump to become red. But it seemed to provoke no reaction at all within her. That is, until the final swat from a hoof was brought down. This one landed with what seemed like an especially painful smack, either because it had hit a particularly sensitive spot on the rump, or because the rump as a whole had already taken quite a beating.

There was silence for a moment, then a faint sniffle. Within seconds, the mighty Limestone Pie had been reduced to tears. And as her eyes were stained red from the constant crying, her padding was pulled back up and she was floated over to a small stool nearby to sit upon. She was made to face a corner of the bedroom, her still sore bottom the only thing anypony could see.

But Twilight knew better than to laugh or take any pleasure from the earth pony's punishment. Especially when the padded alicorn knew that she was going to be subjected to a similar fate. Even though she knew it was futile, she tried to make a run for it. It of course accomplished nothing. Like Limestone before her, she was brought before the sun princess and had her diaper pulled down. She then saw Celestia raise her hoof into the air, ready to bring it down hard upon Twilight's rump. "W-wait, Mommy!" She whimpered in protest. "I... I..." She managed to force out! "I have to use the potty, now!"

Princess Celestia just replied. "I'm not going to fall for that, Twily. You're not getting out of your punishment." And she began to spank Twilight repeatedly. Unlike with Limestone, she didn't have to work as hard or as long to reduce the padded pony in her presence to tears, let alone turn her whole rump red. "You should've just come and gotten me, Twily. I know I didn't respond right away to Limestone's behavior. But fighting her over it is still wrong. Two wrongs don't make a right. I know how much Smarty Pants means to you. And had you come and gotten me instead of fighting Limestone, we could've resolved this whole thing without anypony needing to be punished like this. Do you understand?"

"Y-yes, Mommy!" Twilight sniffled as the swatting ceased and her padding pulled back up over her posture. It was a good thing that happened, because within seconds she felt her tail hike upwards. And with an audible fart, her diaper sagged and began to bulge in the back, a powerful stench of manure filling the air. She couldn't believe it: She was actually messing herself in front of Princess Celestia!

"Oh, Twily!" Celestia exclaimed as the sour note reached her nostrils. "You really did have to go, didn't you?"

The stinky alicorn sobbed, whimpering softly. "Y-yes. It happened so fast. I tried to stop it, Mommy. Really, I did."

The sun princess just gently stroked Twilight's back, trying to calm her down and comfort her. "It's okay, Twily. You couldn't help it. As I've told you before, it's not healthy to keep things held in. If you have to go, you have to go. That's why you have a diaper. It's great that you want to try to use the potty for me, I appreciate that. But I don't want you forcing yourself not to go if you really have to go," She then floated the alicorn in a dirty diaper into the air. "Let's get you cleaned and changed before you get a rash."

"Does this mean I don't have to sit in time out?" Twilight asked in a hopeful tone.

The alicorn mare with a majestic white coat shook her head from side to side. "I'm afraid not, Twily. You still disobeyed me, and you still need time to reflect on why that was wrong. But that can wait until after we've changed your diaper."

Despite how sore her rump was from the spanking, Twilight was still very glad to be changed into a fresh diaper. It didn't make sitting on a stool and facing towards a wall for time out any more bearable, though.

Princess Celestia, for her part, could only reflect on the behavior she had witnessed from her fellow alicorn. "I know Smarty Pants meant a lot to Twilight, but there's no reason for her to have fought Limestone over it the way she did," She thought to herself. "Perhaps I should have another talk with Luna, just to make sure she hasn't noticed something else troubling. Twilight's behavior is mostly just her acting the part, right?"

Well, those were thoughts for another time and place. For now, the sun princess kept a watchful eye on the two padded ponies in her presence, making sure neither of them tried to run away or otherwise get out of their punishment. At last, she was satisfied that both had had quite enough time to reflect on their behavior and where they had gone wrong. "Alright, my little ponies," She said in a sincere and somber tone. "Time out is over. You can both get up now," And as she watched them do so, she asked them. "Is there anything you'd like to say?"

With cheeks still flushed pink with embarrassment, Twilight apologized. "Yes, Mommy. I'm sorry we fought and didn't listen to you."

And Limestone apologized with what sounded like sincerity. "I sowwy fow being bad. Not nice, won't do it again."

Satisfied with the response, the sun princess sweetly declared. "Good. See? That wasn't so hard to say, was it?" She then floated Smarty Pants down from the tall shelf she'd been placed upon. "Now then, if you both promise to share and play nice, you can have Smarty Pants again," To Limestone she added. "And Limey, you have to remember to ask Twily first. Smarty Pants was hers to begin with."

"Play nice with me, please!" Smarty Pants pleaded. "I'm very sensitive, really."

"Sowwy, Smawty Pants," Limestone Pie apologized. "I pwomise I'ww pway nicew with ya."

Twilight smiled, clutching the old doll close to her chest. "I'm just glad you're okay, Smarty Pants."

"Sorry if I made you worry, Twily," Smarty Pants replied. "And I'm sorry you got into trouble because of me."

The padded princess just protested. "It was my fault. I shouldn't have been trying to fight," And she was quick to change the subject, asking the old doll. "Whaddya say we get back to our tea party? We never actually got to make the tea."

And the regressed earth pony mare sheepishly asked. "Can I join? Me wanna pway with ya and Swamty Pants."

With a goofy grin and a giggle, Twilight giddly proclaimed. "Oh of course you can join us, Limey. There's always room for more guests at our tea party." And she shuffled away, Smarty Pants in tow, ready to start the pretend tea party with her new guest.

The tea party progressed without fanfare. Twilight took the liberty of introducing Limestone to all the guests who had been at the party previously (before it had been rudely interrupted). And they were all glad to have the earth pony mare among them to partake in the festivities.

Then, suddenly, right after the drinking of the imaginary tea, something unexpected happened. It seemed as if the far away look in Limestone's moderate amber eyes faded, and she stopped drooling. She shook her head from side to side and rubbed her eyes, as if she were just waking up from a long nap. Looking around the room, the earth pony mare with a bluish-gray coat seemed to be stricken with a sense of surprise and confusion. "...Where am I?" She asked as her lisp seemed to suddenly vanish.

Twilight looked to the earth pony mare with surprise. "What do you mean? You're here with me, Limey."

"Limey?" Limestone blinked, before looking down to herself and taking notice of what was clad firmly around her rump. She groaned and growled ever so faintly. "Ugh, really?!" She complained, turning her eyes toward Princess Celestia off in the distance. "Look, I know I was making a fuss about the diapers and everything, but you didn't have to go and regress my mind like that! You just told me it was going to help me relax!"

Celestia admitted with a bit of a snicker. "Well, it did, didn't it? It's not really my fault, I had to make the spell stronger because your mind was so resistive to the suggestions I was trying to implant. It seems almost as if you were trying to fight the very idea of going back to diapers."

The earth pony mare let out a sigh, sinking into her padding. "Yeah, I did. But can you blame me? I'm the oldest one among my sisters. I was supposed to be the first to master everything when it came to growing up. But Maud was the first one to get out of diapers, and the first one to master use of the flush toilet. And then Pinkie Pie ended up being the first one to leave the rock farm. Meanwhile, Mom and Dad more or less retired and left me to run the farm all on my own. I mean, I liked it, don't get me wrong. But why did it have to be me? Why couldn't it have been somepony else? Marble never put up a fuss about anything, and neither did Maud. Even Pinkie would've been happy to come back to the rock farm to help Mom and Dad out," She groaned. "But no... because I was the oldest and because I didn't leave the rock farm when I was supposed to, it all had to fall on my shoulders."

The padded princess let out a gasp! "Oh my gosh! I never knew it was like that! Whenever Pinkie Pie talked about your family's rock farm, she made it sound like your parents were nothing but supportive and understanding."

Limestone lamented. "Yeah, they were. At least when it came to what Maud and Pinkie wanted. I think Mom and Dad knew before they did that they weren't happy with life on the rock farm. Both of them felt like they had to grow up sooner than they wanted to. And it's all my fault they felt that way. If I hadn't been such a late bloomer in every aspect, Mom and Dad never would've had to rely on Maud to teach the rest of us how to use a flush toilet, or Pinkie to teach us how to laugh and have fun. Heck, Marble even lucked out and got to go back to diapers. I was so jealous of her because of it. It made me wish I could do the same. But of course, my body wouldn't cooperate."

Twilight trotted over, giving Limestone a hug. "It's okay, Limestone. Your parents aren't here now. And you're not the only one among your siblings who's wanted to go back to diapers. There's no reason to be a grump about it."

The earth pony mare sighed again, hanging her head in shame. "I know, I know. And that's not an excuse for the way I acted while I was regressed. I was a real terror back when I was a foal, especially before Maud and the twins came around. Having all the attention of the family, it felt so nice. I let it all go to my head, just like I let running the rock farm go to my head," She then turned to Princess Celestia. "You don't have to do anything nice for me, princess. I know I didn't behave myself as well as I should have. If you wanna tell Mom and Dad how I acted like a brat all day, you can," Her ears fell flat against her face. "I'll accept my punishment."

But the sun princess protested with a firm shake of her head. "Don't be silly, Limestone. You've learned your lesson, I can tell. If you hadn't, you wouldn't be apologizing now," And she added with a sincere smile. "I'd be more than happy to have a talk with your parents about giving you a break. It isn't right that they should place all their hopes onto you. You're just one pony. You should be allowed to have a life of your own."

"Hey, I like running the farm!" Limestone insisted! "Sure, maybe it can be stressful sometimes, and maybe I would've liked to have been given the choice. But somepony's got to do it now that Mom and Dad can't. It's just that..." She blushed. "Sometimes, even I can use a break from it all, you know?"

"Perfectly understandable," Celestia agreed. "Even I sometimes can grow tired of my responsibilities, as important as they may be. That's why I'll always be grateful to have Twily here to help me unwind," She trotted over to Limestone. "You're a very strong pony for putting up with everything for so long, Limestone. But it can take an even stronger pony to admit how they really feel. Just be honest with your parents when you feel like you can't handle your responsibilities on your own. I'm sure they will understand."