Author's Note

And thus, the Pie sisters have all been put back into diapers! Kind of surprised Marble Pie had to wait for both Maud and Limestone, then again it seems like if it's not Pinkie the Pie sister who gets the most diaper art tends to be Maud (likely owing to her popularity and more reoccurring appearances).

As usual, it's Scootabom1 who came up with the idea for what to do with Marble: Having her slightly regressed and made to see Twilight and Princess Celestia as family, and her and Twilight having a blanket fort sleepover together (albeit during the day). Marble being in college is a nod to the IDW comics (though they never said where exactly she went).

Now, I want to let everyone know this will be the last chapter of the fic for 2024, there will not be a December chapter. Let me repeat that, there will NOT be a December chapter. The next chapter will not be published until at least the second or third week of January. To make up for the skipped month, you can vote for up to two ponies this time around. And you can all decide whether you want them to be two separate chapters, or one combo chapter. Whoever you vote for first will get a whole vote, and whoever you vote for second will get half a vote. Depending on whether others specify combining characters or not will determine if it's one joint chapter, or two separate chapters like when this fic debuted.

And this is just a friendly reminder that Starlight, Sunburst, Trixie, and Discord are among the characters ineligiable for consideration under any circumstances.

Characters ineligable under any circumstances:
Starlight Glimmer
Discord
Trixie
Sunburst
Cutie Mark Crusaders
Flurry Heart
School aged or younger children (i.e. Cake Twins)
Characters introduced after Flurry Heart (Starswirl the Bearded, the Pillars, Star Tracker, Mudbriar, etc.)
Equestria Girls characters other than Sunset Shimmer/the Dazzlings
Princess Celestia

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
Prince Blueblood
Marble 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, Soarin - One vote
Sassy Saddles, Fleur De Lis, Party Favor - One half vote

Little Marble (Marble Pie)

Princess Celestia playfully gave Twilight's padded posture a pat, whilst speaking in that cooing, motherly tone of hers. "There we go, Twily. All nice and clean again. And you were only a little wet, I hardly would've noticed if you hadn't told me."

"W-well, I tried to use the potty, honest," Twilight admitted in what sounded like an only somewhat exaggerated tone of embarrassment. "I didn't want you to be mad with me, Mommy."

The sun princess smiled and reassured her fellow princess. "Twily, you know I'll never be mad with you for having accidents. It's why you're still in diapers, after all. And I don't want using the potty to feel like a chore to you. I only want you to do it if you really feel comfortable doing it. Not using it isn't something you should feel ashamed of, no matter what it is you do in your diapers."

"But I want to make you happy, Mommy." Twilight insisted with a smile.

Celestia just cooed. "I'm already happy as it is, Twily. I will always love you no matter what you do. Don't you remember that, my little pony?" Her tone of voice at the end sounded slightly concerned, revealing that underlying worry that she had not voiced to anypony else (not even to Luna, who as of yet had not said anything further about Twilight's mental state).

The padded princess nodded. "I do, Mommy. But sometimes I forget," She playfully swished her tail and giggled, before running off to grab Smarty Pants. "I'm back, Smarty Pants. Sorry I made you wait."

Smarty Pants just replied in that exaggerated tone of hers. "I don't mind waiting, Twily. When I'm with you, it feels like time stands still. Besides, I wouldn't want our playtime to be interrupted by a diaper rash."

The elder alicorn smiled anew as she then trotted up to Twilight, all the while summoning up some paper and a box of colored pencils. "Alright, Twily. Can I trust you to stay here and do some doodling for me? Mommy needs a little bit more time to get your surprise ready for you."

"Is it another playmate?" The padded alicorn asked in a hopeful tone.

The alicorn mare with a majestic white coat just flashed a knowing wink as she cryptically replied. "Wait and see. Just stay here and try not to make a mess, okay?"

Twilight gave a salute, before plopping promptly onto her padded posture, delighting in how it crinkled and compressed. She even briefly distracted herself by poking it with a hoof, making it crinkle and compress even more.

Satisfied that her fellow princess wouldn't wander off, make a mess, or otherwise get into trouble, Princess Celestia simply lit her up and disappeared in a flash of light.

Just like that, Twilight and Smarty Pants were alone in the bedroom. But neither of them really minded it much, Twilight simply grabbed some of the colored pencils out of the box with her hooves. She gave no thought at all to using her horn, even though she knew that usually when wielding pencil or pen she would normally use her horn for greater precision. This was one situation, however, where precision was not necessary. And so, she clumsily doodled with her hooves, no particular image was in her mind.

A minute or so later, there was another flash of light! Celestia reappeared in the bedroom in all her glory, and accompanying her was an earth pony mare with a turquoisish gray coat. Her grayish violet eyes were hidden behind her locks of two toned grey that matched her tail perfectly. And there of course was her cutie mark, three purple marbles, which just barely poked out through the thick, white diaper that was taped firmly around her hind quarters, hugging it tightly.

Twilight put down her pencils and looked up, eyeing the newcomer with a mix of shock and happiness. "Is that my new playmate, Mommy?!" She asked in a hopeful tone.

The padded earth pony whimpered and seemed to shrink from Twilight's gaze, retreating behind Princess Celestia with a clumsy waddle and a faintly audible "Eep!".

The alicorn princess with a coat the same white as the diapers just laughed lightly, before ushering the newcomer out. "Now now, Marble," She said in a reassuring coo. "There's no need to be shy. This is Twily. Go on, say hello."

Marble hesitated for a moment or so, before forcing out an "Okay, Mommy," in what sounded like a faintly detectable lisp. She then toddled forward, extending a hoof towards her fellow padded pony. "H-hi, Twily," She greeted as best she could. "I Marble. Nice to meet ya."

Twilight grabbed Marble's hoof and shook it quite gently. "Nice to meet ya, Marble," Then she blinked in surprise, and in a normal tone of voice asked. "But did you call Princess Celestia 'Mommy'? You know she's not actually your mommy, right?"

Marble whimpered again, but managed to force out. "Mommy cast a spell to make me see her as mommy," She then apologized, speaking somewhat normally. "Sorry. I'm still a little shy. I-I... I'm getting better at not being shy, but sometimes I need a little help. M-Mommy told about you and her do, and asked if I'd be your playmate. I... actually didn't hesitate to say yes. I kind of wanted to go back to diapers again."

The padded princes giggled. "Yeah, I know what you mean. Diapers are so comfy." She briefly swished her padded posture to emphasize her point.

Marble nodded back. "Mmhmm. So because Mommy cast that spell, you and I are family. I guess that means you're a big sister, just like Limestone, Maud, and Pinkie."

At that the padded alicorn excitedly exclaimed! "Oh my gosh! I never even thought of that! But you're totally right, Marble!" She started bouncing all around, all but shouting at the top of her lungs! "I get to be a big sister! I get to be a big sister!"

Celestia chortled as she gestured a hoof to temper her fellow alicorn's enthusiasm. "Easy, Twilight. No need to blurt it out for the whole castle to hear."

Twilight ceased in her bouncing, blushing as she did so. "Oh, sorry," Once she'd fully recovered from her brief bout of embarrassment, she then turned her attention to Smarty Pants. Using her magic, she grabbed the old doll and held it before her fellow padded pony. "Smarty Pants, this is Marble. She's gonna be my new little sister today. Isn't that lovely?"

"Wow, Twily!" Smarty Pants exclaimed in amazement. "You're a big sister now? You're growing up so fast. I barely even recognize you anymore."

Marble, for her part, didn't seem to be surprised in the least by how the doll was able to speak (or who was actually behind its voice). "Hi, Smarty Pants," She greeted with a wave, briefly blowing the bangs out of her eyes. "I wish I'd have known you were going to be here too. I would've brought Mr. Pebbles with me," As the bangs settled over her eyes, she whimpered slightly. "But I didn't even bring him with me to college. I was too afraid ponies would find him accidentally and make fun of me for still having him around. I don't really need him, but having him around helps me remember a simpler time."

"Hey, that's okay," Smarty Pants reassured the padded earth pony. "You can share me, just as long as you don't play too roughly. If you're a part of Twily's family, then that means you and I are family too."

The earth pony mare with a turquoisish gray coat just replied with another soft "Mmhmm.", smiling as she did so.

Twilight then took the liberty of asking her new playmate and "little sister". "So, what do you wanna do today, Marble? What do you like to do for fun?"

"Fun?" Marble blinked in what seemed like genuine surprise. She then put a hoof to her chin, appearing to be deep in thought. As she thought and contemplated, a brief bit of drool seemed to escape her lips. At last, she seemed to settle on an idea, and proposed as she turned to face her fellow padded pony. "We could play fort and have a camp out."

"But it's not night time," The padded princess pointed out as she looked out the window, seeing that it was at best just slightly past noon given the position of the sun. "And I already built a pillow fort once."

The padded earth pony mare just replied. "Well... we could make a blanket fort. And then we can pretend to camp out. We won't have to actually get dirty or set up tents."

"That sounds like a great idea!" Princess Celestia said with a coo. "I'll even help you two get set up. Then, that way, I can keep an eye on you both and make sure you don't get into trouble." And so it was arranged.

Working together with Princess Celestia, Twilight, Marble Pie, and Smarty Pants went around the bedroom. Together, they grabbed blankets and a few pillows off the beds. They then spread the collected blankets out on the ground in the middle of the room, creating a nice little area of soft blankets to lay upon.

Using their imagination, the padded ponies conjured up the image of a vast fortress in the middle of what was otherwise untamed wilderness. And of course, no fort would be complete without lookout towers, gates, and a place for the ponies dwelling within the fort to eat, sleep, and play (there was no need for bathrooms given that they were already wearing them. Besides, ponies living out in the wilderness just used nature as a toilet, though they had to be careful not to accidentally wipe with poison ivy or poison joke).

Soon, the great blanket fort was ready for its occupants to enter into it and camp out inside of its limits. Twilight, Marble, and Smarty Pants all waddled up to the fort's gates and stood before them.

The gates rose up before the trio of ponies wishing to enter the fort, and they wasted no time in waddling into the fort interior as the gates then slammed shut behind them. They were now safely within the blanket fort's confines, protected from the dangers of the surrounding wilderness.

Princess Celestia trotted up to the outer limits of the fort but a moment later, smiling as she watched her charges settle atop the many blankets and settling onto the pillows they had brought with them. She could very easily just waltz right in, there was nothing that stopped her from doing so. But she thought there would be no harm in humoring the two padded ponies (and Smarty Pants). So she cleared her throat and raised up a hoof, pretending to knock against the walls of the fort in order to demand that she be allowed to enter.

Smarty Pants was floated up towards the sun princess, eyeing her with what seemed to be suspicion. "Who is it?" She inquired in a gruff, almost authoritative tone of voice.

"It's me, Princess Celestia. I am here to bring supplies and reinforcements for the ponies inside." The sun princess replied.

"Just leave it all outside, we'll send somepony out to bring it all for us," Smarty Pants insisted. "Now go away!"

Celestia pretended to be offended by the suggestion. In a dramatic, exaggerated tone of voice, she exclaimed! "What?! You're ordering me to go away?! Me?! The very ruler of Equestria and the pony responsible for raising and lowering the sun?! I am a princess, royalty even! I deserve to be treated with more respect!"

Smarty Pants just waved a hoof, acting as if she were wielding a spear! And she repeated her earlier demand. "Go away! Your title means nothing here! Nopony gets inside this fortress after the gates are closed!"

"Oh really?" The sun princess retorted with what seemed like a playful, mischievous smirk that was spreading across her face. "Well I didn't come all this way with these supplies just to be told to leave," Eyeing the doll, she declared in an ominous tone of voice. "This is your last chance to avoid making a costly mistake. Let me in, and nopony gets hurt."

The doll refused to be intimidated. "Orders are orders. If you won't leave willingly, we'll just have to make you leave, by force!" She turned back towards the fort's interior and hollered at the top of her lungs! "Guards, ready your spears! We must drive this attempted invader away!"

Yet the alicorn mare with a majestic white coat only replied. "Big mistake." Then she lit up her horn, and in the blink of an eye teleported right into the middle of the fort and was standing right in front of both Twilight and Marble Pie.

Twilight and Marble Pie exchanged mutual gasps and looks of horror! They now found themselves completely at the sun princess' mercy.

"What naughty foals you are, trying to attack your mommy," Princess Celestia playfully scolded as she quickly lit up her horn and pulled her charges close. "And you know what naughty foals like you get?"

Twilight whimpered, kicking all about in her pampers as she pleaded. "No, Mommy! Please! We didn't mean it!"

"Please, Mommy, have mercy!" Marble pleaded.

Celestia just replied with a giggle, then took a deep breath as she brought her mouth towards Twilight and Marble's chests. "Say hello to my little friend: The tickle monster!" She exclaimed, and then proceeded to promptly blow raspberries all over their stomachs, making her padded charges squirm and giggle with uncontrollable laughter.

"S-stop! Please!" The two padded ponies tried to plead in between fits of laughter. Alas, their pleas went unanswered, the tickling continued without end. They were laughing so much and so hard that they were starting to get tears in their eyes.

Meanwhile, Smarty Pants could only look in horror! She was powerless to stop the merciless tickle attack.

Suddenly, amidst the howls of hysterical laughter, a new sound filled the air. It started quietly, but grew louder and more noticeable by the second. It was a hissing sound. And it was accompanied by noticeable dark patches that were appearing on both Twilight and Marble's diapers. The patches first appeared near the seat of the padded undergarments, yet slowly expanded until both diapers were completely swollen and darkened. Then and only then did the tickle attack finally stop.

"Whoopsie daisy!" Princess Celestia teased. "It seems my foals couldn't hold it in and opened their floodgates. Thank goodness I had them diapered, or they would've peed on my nice clean floors."

Marble threw her hooves over her face in shame and embarrassment. "Sorry, Mommy."

The elder alicorn just smiled, gently reassuring the soggy padded ponies. "It's alright, you couldn't help it. And it's not good to hold it in all the time," Then, lighting up her horn once again, she carried both foals away. "Let's just get you both changed and cleaned up. Then we can resume your little camp out together."

Princess Celestia was quick as a flash when it came to the diaper changes. In no time at all, she had wiped both Twilight and Marble's soggy rumps clean, and had strapped them up into fresh diapers. "All done." She said with a smile, patting both padded ponies gently on the forehead.

Twilight and Marble then wasted no time in returning to their blanket fort, and were quite relieved to be allowed back in without a fuss. They soon resumed their camping out spot in the middle of the fort, protected by the walls and the guards.

Marble sighed as she lay back upon her pillow, gazing up towards the open sky (in actuality the ceiling). And for the moment, she seemed content to just lay there, her padded posture sticking up for all to see. She didn't seem to have a care in the world or a thought in her head.

The padded princess smiled as she saw fit to imitate her playmate's overall posture. Then, after a moment or so, she decided to break up the unofficial spell of silence by saying to the padded earth pony next to her. "You're really good at this, Marble. It's like you've done this all before."

Marble turned her gaze ever so slowly towards Twilight, once again blowing the bangs out of her eyes. "W-well," The words seemed to be slow to leave her mouth, as if it was hard for her to gather her thoughts. "I'm... sure you already know from my other sisters. We didn't really have diapers or foal toys growing up. The diapers we did have were second hoof, hoof made and passed down from other branches of our family. That's how Granny Pie came to live with us, she was there to help Mom and Dad after Pinkie and I were born so that Mom and Dad could spend more time with Limestone and Maud."

Twilight nodded, remembering what she had picked up from Pinkie, Maud, and Limestone. It would seem that the simplicity of the Pie family's rock farming lifestyle extended even into places where you might have expected some deviation to include modern conveniences.

The earth pony mare with a turquoisish gray coat shut her eyes as she continued, appearing to draw on memories long since passed. "Of course, once we got the flush toilet installed, we had to learn how to use it. And Maud was the first one to really figure it out. Limestone, meanwhile, kept teasing me about how there was a monster that lived inside of it and ate foals. It was only later that I learned she was doing it because she was jealous of Maud and Pinkie for mastering use of the flush toilet before her. And she wanted to try to keep me from beating her in that regard."

"Yeah, older siblings can be such poopy heads sometimes," Twilight giggled. "B.B.B.F.F. was a lot of fun to play with. But sometimes he could get super competitive, and always boasted whenever he won at anything. Turns out, he had a lot of development issues growing up, which he seemed to forget about whenever he made fun of me growing up."

Marble let out a sigh, opening her eyes slightly. "Well, Limestone did eventually apologize. She's actually kind of nice if you get to know her. And she does do a good job keeping the rock farm running so that Mom and Dad don't have to worry about it. She didn't even put up a fuss when I went away to college, leaving her to live on the rock farm with just Mom and Dad for company. But I'm sure even she gets lonely sometimes, she's just too proud and stubborn to admit it. As for me," She looked to herself and to her padded plot that was still sticking up in the air. "Being in college has given me a lot to think about?"

"Is it true you went back to diapers because you were wetting the bed?" Smarty Pants asked. The doll had by now given up on her patrols and had settled in next to Twilight, apparently content that the fortress would do its job of keeping unwanted guests away.

The padded earth pony nodded, blushing slightly as she did so. "Yeah. And I was really glad when Maud wore diapers to get Limestone to stop teasing me. I know that couldn't have been easy for Maud to do, given that she had the fewest problems with growing up and getting out of diapers. Of course, I eventually grew out of bed wetting and gave up diapers again. At the time, I thought I'd never want to wear them ever again, let alone actually use them. But after I went away to college, I found myself starting to long for the carefree times I associated with diapers. So I started wearing them in secret in my dorm room. And now," She dreamily sighed. "Now I'm wondering why I ever thought getting out of them was a bad idea. Don't get me wrong: I'm glad I was potty trained. But being back in diapers just feels so much better."

Twilight nodded back and smiled. "Well, it's a good thing you have me and Mommy. Here, you can be in diapers and do whatever you want. Everything's taken care of for you."

Smarty Pants chimed in. "You're a lot nicer and quieter than some of Twily's other playmates, Marble. You really are a good little sister."

Marble seemed taken aback by such a statement! As the bangs settled over her eyes once again, she asked the padded princess and Smarty Pants. "You really think so?"

Both Twilight and Smarty Pants nodded as Twilight then declared. "Think so? I know so, Marble."

Marble smiled as she sat up all the way, then waddled over to her fellow padded pony and gave her a hug. "T-thank you," She spoke, slowly sliding in that lisp she had briefly displayed earlier. "You so nice, Twily."

The padded alicorn just returned the hug full force and said nothing at all.

Princess Celestia then broke up the silence by clearing her throat, revealing several large trays held aloft in the soft glow of her horn. "I hope you're hungry, my little ponies," She cooed. "Because I have brought enough food to fill an entire ballroom. We are going to feast!"

Twilight sniffed the air, her mouth watering at all the tempting and tasty treats that she could smell. She couldn't wait to consume them.

Celestia promptly floated the trays over, placing them in the middle of the blanket fort as she moved to sit down. She then floated over some bibs, tying them around the necks of both her charges. "Don't want my foals making a mess." She smiled, before lifting up the lids of the trays one by one.

Freshly cut fruits and vegetables rested on the trays, as did several large jars of different flavored foal foods, not to mention fresh applesauce. The only form of refreshment that appeared, however, were two large baby bottles filled to the brim with what appeared to be warm milk.

The sun princess proceeded to unscrew the lids of the jars of foal food and dip plastic spoons into the colored goop. "Alright, my little ponies. It's time for your num-nums. Now open wide for the aeroplane."

Marble and Twilight fully cooperated as the various flavored foods were deposited onto their tongues. Savory sweet tastes such as bananas, pumpkin, potatoes, and even sweet corn all tempted their taste buds. It was overwhelming in a good way! And the applesauce they were served afterwards was just as delicious. Then they were given their bottles of milk to wash it all down. And the milk's rich, creamy taste made it hard for them not to drink down the entire bottle's worth. Lucky for them, Princess Celestia took the bottles away when they were half empty. "If you drink down all your milk, you won't have any left for the fruits and veggies." She told them, then sat back and let them take hold of the remaining food with their hooves.

Twilight paused momentarily in her eating as she saw fit to ask something she had noticed about the milk. "Mommy, did you put your milkies into our bottles?" She inquired of her fellow alicorn.

Princess Celestia happily nodded. "Of course, Twily. I need to make sure my foals get their nutrition, after all."

"Ah, that's why the milk tasted so good!" Marble exclaimed as she licked her lips. "Although, I remember that my other mommy used to put little bits of crushed rock into my bottles. She said it helped my teeth and my jaw grow up big and strong. And she was right."

"Hm, perhaps I should consider doing that from now on to help Twily's teeth and jaw." The sun princess pondered, before turning her attention back to Twilight.

The padded ponies were amazed soon afterward when, even after eating all the fruits and veggies and drinking down the rest of their milk, they still didn't feel quite "full" just yet for lack of a better term.

The sun princess seemed to know this. Because she stood up slowly, lit up her horn again, and declared. "I believe my foals have earned a special treat for being so well behaved today." She then brought forth a tray that held a large, goopy substance colored a dark brown.

Both padded ponies' eyes went wide as they exclaimed in unison! "Chocolate pudding!"

The alicorn mare with a majestic white coat smiled as she gave a confirming nod. "Indeed it is. Go ahead, eat up."

Twilight and Marble needed no further incentive, and dug into the chocolate pudding with their bare hooves. They seemed not to care for how much of it they were smearing on their faces and on their bibs. It was too irresistible for them to think about eating carefully. They just devoured as much of the pudding as they could, until their stomachs felt so full they could burst. Then and only then did the two padded ponies rest, giving out hearty belches as they seemed satisfied with what they had done.

Celestia just giggled, before floating over a prepared wet rag colored red and using it to wipe the face of both diapered ponies. After that, she watched as both mares waddled around the fort for a little bit, before yawning. All that food and milk was working like a charm. So she just floated over some additional blankets, and made sure Smarty Pants was securely tucked into the hooves of Twilight. Then she kissed both Twilight and Marble on their foreheads, gently cooing. "Sweet dreams, my little ponies." She then rose slowly from her current position, trotted to the light switch, and flicked it off in order to cast the entire bedroom into darkness.

This little playdate/sleepover had gone off without a hitch. And she was already thinking of how she could repay Marble for having played her part so willingly in spite of needing a little bit of magical assistance to come out of her shell.

The next day, Marble Pie woke up in her dorm room in Fillydelphia, yawning as she wiped the sleep out of her eyes. Yesterday had been the most fun she could readily recall having in many years.

To the earth pony mare with bangs' surprise, there was what appeared to be a letter of some sort sitting on a small stand near her bed. Being naturally quite curious, she picked it up and examined it carefully. It read as follows:

Dear Marble Pie,

Thanks again for agreeing to be Twilight's playmate, and for agreeing to keep her secret a secret. I'm sure you need no incentive to avoid sharing it with ponies not already in the know. And I know it couldn't have been easy to let me help you feel more comfortable and at ease.

Rest assured, everything you shared with Twily and I yesterday will stay our little secret. We won't tell a soul to anypony who doesn't already know.

However, even though I'm sure you don't need any sort of reward, I still feel like you deserve something to help me express my gratitude. So I took the liberty of arranging for some very special guests to come over for a very special party just for you. Hope you enjoy it.

Yours truly,

Princess Celestia

Marble put down the note and felt her heart skip a beat! "Could it be?!" She thought to herself as she tried to think about who the sun princess was referring to.

Those thoughts were soon interrupted by a knock at what the earth pony mare only now realized was in fact an otherwise empty dorm room. Of course, everypony else had gone home for the holiday. And she had been planning to do the same, before Princess Celestia had by chance asked her to be a padded playmate for Twilight.

Come to think of it, how had the sun princess even known to ask Marble in the first place? Marble was so sure she had gone to great lengths to keep hidden her secret about wearing (and sometimes using) diapers. So how had Celestia of all ponies managed to find out without needing to ask Marble directly? It couldn't just be a lucky guess.

As the turquoisish gray coated earth pony mare pondered this and other puzzles, she nevertheless reached the door of her empty dorm room and opened it. And what she saw waiting for her on the other side made her eyes widen in disbelief! It was too good to be true!

Standing there, clad in nothing but thick, white diapers, were all three of Marble's older sisters: Limestone, Maud, and Pinkie. Maud had even taken off that tunic she was always so fond of wearing.

Pinkie Pie was the first one of the three padded sisters to speak up! "Hiya, Marble! Princess Celestia told us we might find you here!"

"W-what?!" Marble blinked slowly, trying to process her complex emotions.

Limestone giggled as she trotted forward, grabbing hold of Marble and pulling her close. "Hey, there's no need to hide it. We're all back in diapers now. And we know you've wanted to go back to them too. So thanks to a certain somepony tipping us off, we decided to visit you and have a diaper party."

"It was Pinkie Pie's idea," Maud pointed out. "And this way, we don't have to go on hiding our secrets anymore. We were gonna have it at Sugarcube Corner now that Pinkie's in charge of it. But she felt it would be better to come here and hang out with you, seeing as we haven't really gotten together as a family in a long time."

Marble was utterly speechless! She couldn't think of anything to say!

Pinkie smiled. "I know, I know. It totally freaks your frizz, Marble! Sorry we didn't write to you sooner, but I wanted it to be a surprise. So... surprise!"

Once the shock of the sudden revelation wore off, Marble Pie managed to force out with a sheepish smile. "T-thank you... all of you. It means a lot that you'd... well... you know. You really didn't have to."

"Hey, what are sisters for?" Limestone pointed out with a playful giggle. "Besides, we can all see why you like diapers. It's nothing to be ashamed of."

"So you should go get changed, Marble," Maud encouraged with something of a smile. "We're going to have so much fun together."

And indeed, Marble needed no further incentive to slip back into her dorm room. She dove right under her bed, and without bothering to make sure nopony was around she quickly pulled out an already opened box of Silly Filly brand adult diapers. In a matter of seconds, she had taken hold of a fresh diaper from the box, and effortlessly taped it around her rump so that it hugged it tightly. Now she was ready for another padded playdate: One spent with all of her sisters.

Was this a dream? No, Marble knew in her heart that it was real.