Luna smiled as she walked into her room. it had been about a week or two since she had been freed from the imprisonment of nightmare moon, and even though she wasn't used to most things nowadays, she was happy. she looked out to her balcony and saw that Celestia had already started to lower the sun.

"it's just like Celestia to start her tasks early," Luna said as she walked to the balcony and put on her royal crown. with what seemed to be a simple glow of the alicorn's hour, the empty sky had disappeared and soon a full night sky had appeared, complete with stars and her old prison- the moon. the alicorn smiled for a moment and looked at her lovely night. that was until she felt a presence in her room with her, she turned around and saw.... nothing, she saw no-pony at all, only herself, in her mirror, "I must be imagining things." she said to herself as she turned around with her eyes closed, and opened them again to she the mare that she once was standing in front of her,

"boo." nightmare moon said, which sent the princess of the night to the ground

"h-how are you here? you were defeated by the elements of harmony!" Luna proclaimed to the black-coated mare

"you honestly thought I would let myself be defeated by those things twice? ha! as soon as we were sent to the moon, I created a spell to shield myself from them, but it would free you." Nightmare Moon glared down at the alicorn and walked closer

Luna backed up some, "no! You couldn't have! That level of magic-"

"Would have been impossible? Yes, I thought so too. It took a while, but I perfected it." Nightmare moon walked closer again, chuckling to herself

Luna gulped and backed up more, her hour glowing slightly, "w-what do you want?!"

"The only thing keeping me from taking over Equestria is you! See, only one mare can have enough magical energy to move the moon. That's why when i- we were sent to the moon, Celestia gained the power. So by taking control of you, I will be able to make the eternal night!" the mare of the night once more walked closer to the mare on the floor

Luna backed up more, only to hit a wall. This was it, if she didn't release the spell she was charging, she would be done for. Luna closed her eyes and the spell shot out of her hour in a beam of pure magic. It was heading straight to nightmare moon until she just suddenly disappear like she wasn't even there. Luna sighed, it was in her head, all of it! Well, most of it, seeing as she was still on the floor by her wall, and a beam of magic had hit her mirror and now was aiming straight at her, "buck."

Celestia sat in her room, ready to fall asleep, that was until she saw a blast of lightish blue magic come from out of her window, the sun princess knew whose magic that was, and it scared her, "Luna!"

Celestia instantly got up and used her magic to teleport to Luna's room.

Celestia looked around the darkroom, "Luna? Luna?!" She yelled, "Luna where are you?!" She felt a few tears fall down her muzzle

Celestia Than fell down to the ground, tears falling down her muzzle faster and faster. She didn't know what had happened, maybe an assassin was hired to kill her, but tried to do it well she was in the dream realm and caused her to lose control and sent them both lost in the dream realm forever.

Her mind kept up with different ideas of what could have happened, until she felt a small hoof on her side, and a quiet voice saying, "don't worry Tia, I here."

Celestiainstantly looked down at her side to see a small, blue foal, who didn't even look a year old, "l-Luna, is that you?"

The foal looked up at Celestia and nodded, speaking a little bit louder than before, she said, "Yeah it me, Tia."

The alicorn mare picked up the foal and hugged her, "oh Luna, I thought I lost you again!" A few tears ran down her muzzle. After a couple of minutes, Celestia stopped hugging Luna, "what happened to you, Luna?'"

Luna looked down at her body and blushed a little, she could have told the truth, but she was scared that she would get laughed at, so she decided to lie, "m-me no know, me was bout to go to da dream world, than me just turn to baby!"

Celestia looked shocked, "so you just turned into a baby? Do you know how to turn back?"

Luna shook her head as she was sat back onto the floor, "no, me don't, I-" Luna than stopped talking, and just blushed

"What's wrong luna? Did something happen?" Celestia Asked the baby

Luna blushed, she hoped that her sister wouldn't notice the stain growing on the carpet, around her

Celestia, feeling the wet spot on the carpet also blushed, "Luna, did you have an accident?"

Luna didn't know what to say, she didn't even feel the need to use the bathroom, "yes."

"What Luna, I couldn't hear you," Celestia said. She knew the answer, but she felt too awkward to say it

"Yes." Luna blushed, she was at the edge of crying

Celestia sighed, a blush still on her face, "it's alright that you did luna, I don't blame you. After all, you're a baby right now, " Celestia picked up the baby, "but until we can fix this, I think that there's something we need to do."

Celestia moved luna over to the bed, laying her onto her back, and using her magic to hold her in place

Luna looked at Celestia with a blush, "you not doing what me think you doing?"

Celestia didn't say anything. The alicorn used her magic to grab a towel from the bathroom and get it a little wet. She then picked up the foal's little hooves with one hoof and started to wipe her bottom with the other

Luna blushed as Celestia did so, "tia stop! This embarrassing!"

Even though she heard luna's cries, she continued. Once she finished wiping her down, the towel had a giant yellow spot. Celestia than used her magic to make a diaper appear, "im sorry luna, but this is for your own good."

At this point, luna was screaming at Celestia, "tia, me no need diapee! It one accident! It no happen again!"

Celestia, however, didn't care. She placed the diaper underneath luna's bottom. She then taped both sides snugly around luna's rump, "there you go."

Luna blushed, tugging at the tapes, "stupid diapee! Come off!"

"That won't do anything luna, I made them so they won't come off unless an adult takes them off," Celestia said

Luna blushed a bright red, "take off sissy!" She didn't realize what she said.

Celestia blushed a little being called that but decided not to say anything, "no luna, until we turn you back to normal, your going to wear one of those."

Luna still blushed, "but I no have more accidents."

Celestia sighed, "You don't know that, luna. I'd rather have you wear one of those and not have any accidents than have one on the floor."

Seeing no way out of this, luna sighed, "fine, I wear one till me, adult, again."

Celestia smiled, "Good, now let's go to bed, I'll start to look for a way to cure you in the morning."

"Why you no make it morning wight now?" Luna asked, yawning a little

"You know I can't luna, it only just turned to night about an hour ago!" Celestia giggled a little

"Fine!" Luna said, yawning a little more

"Sounds like somepony is tired." Celestia used her magic to teleport the two to her room

"Why we here, tia?" Luna asked

Celestia smiled, "well, I don't think you can sleep alone in your bed, seeing how small you are, so I thought you could sleep in my bed with me."

Luna yawned again, her eyes felt heavy, "o-otay, that fine."

Celestia smiled and laid down on her bed, setting luna right next to her. The foal had already fallen asleep, "goodnight little luna, sweet dreams."

Author's Note

Sorry if this chapter seems kinda rushed, I finished it in like two days