Sissy

You were sitting at home waiting for your parents to arrive when you heard your little sister call you form upstairs. Groaning as you turned off the TV, you begrudgingly went up stairs to see what she was yelling for.
Entering her room you suddenly feet very disy and fell to the ground, passing out shortly after impact.

When you woke you found yourself sitting in your baby sister's crib. With her playing happily with her toys over by her doll house.
You began to stand up only to fall back down onto your rear. Though you were surprised to hear a soft crinkle and 'puff' sound underneath your bottom. Looking down you gasped to see a diaper around your waist! With a bright pink top that said 'baby' in big colorful bubble letters. The diaper it's self looked like one of your sister's, with Disney characters and pink details as decor. Though this one was bigger, fitting you perfectly.
"May May, come over here and help your older sibling out please!" You called over to your sister, who was wearing her favorite princess dress. To your luck she came over, though she stopped short in front of the crib.
"So you're finally awake!" She smiled, you didn't like the way she smiled.
"Yep, can you let me out now?" You asked nicely, holding she would cooperate with you before your mom got home.
"Sure, but first, smell this!" She laughed before puffing a cloud of baby powder in your face.
You say there in the diaper confused for a sec, before your body forced out everything in you bladder and bowls and it all came flooding into your diaper. You gasped and blushed from embarrassment. What happened?! Did May do something to you?! You had been potty trained for years and hadn't had an accident for about as long.
"Wow, you really had to go didn't you, maybe you need your diapers more than I do." You sister snickered as she brought the bars of her crib down for you. Still not able to stand well you crawled out only for your sister to puff more baby powder into your face, causing another mess to flood into your padding.
"What did you do to me?!" You asked, desperate for a reason why this was happening.
"I made you go potty when ever you smelled baby powder!" Your little sister giggled, " it was getting so lonely being the only one here who wore diapers, so I wanted you to be like me!"
"But what about mom! I can't be in diapers anny more I'm a teen now!" You cried. Your sister giggled and patted your padded butt, smooshing some of your mess into your bum.
"You're a baby now! Mommy will take you out of school and change your diapers, after seeing how much you love them! Then you'll get to smell lots of baby powder, and you'll be in diapers with me!" May smiled, "though you'll loose your potty training as you go potty more and more!"
"That's not ok! What about when you become potty trained?!" You tried reasoning.
"Then you'll be my little sibling! And I'll get to help Mommy take care of baby all day!" May cheered, causing your heart to drop. She puffed more powder at your face, causing even more mush to fall from your behind.
"Oopsie! Baby went potty again!" May clapped as she giggled at your misery.
"Can I please get out of this diaper!" You begged.
"Sure, after we play a game!" Your baby spoke.
"What ever it takes!" You answered.
"Ok, this game is called bomb rush, where we both go in our diapers as much as possible, who ever has the most mess in their diapers at the end wins. If you win I'll reverse my spell and you can go back to your big panties. If I win, you have to smell more baby powder!" May explained.
"Yeah sure what ever, as long as I get out of this thing!" You responded.
"Ok, three ... two .. one . GO!" May cheered, and with that you shut your eyes tight and began pushing as much out of your bowls as possible.
"Y/N!" You heard a familiar voice shout, only to turn around and see your mom, she was stunned to see her oldest, in a diaper, dirty, and saggy with how much was in it.
"MOM! ITS NOT WHAT IT LOOKS LIKE!" you tried to explain, but while getting up you're legs gave out again, causing you to fall down on your butt, squishing your mess all over your bum and padding.
Wordlessly your Mom dropped her bags and picked you up in her arms. She laid you down on to May's changing table and began untapping your diaper. You were tearing up as she looked flabbergasted at the mess your body had made to the pamper. She cleaned up your bottom and privates and then grabbed another diaper to put on you, catching you off guard.
"Your sister told me you wanted to start wearing diapers again this morning, but I didn't believe it until now." Mom said as she slid the diaper under your bum.
"I don't! She was just ma-" you started but your mom put a paci in your mouth and smiled warmly.
"It's ok, baby. I'm happy you won't be growing up as fast as I thought you were." She smiled before heavily powdering your diaper and privates, before taping up your second diaper. She then sat you up, causing you to get a wif of the lingering baby powder, and with that your messed yourself once again, this time with a small squishy sound as the poo dropped into your padding. You began to bawl, to which your mom picked you up into her arms once more and began to bounce you gently in her arms to calm you down.
Though it worked to your surprise and you began to drift off to sleep, making more messes in your padding as your mom now smelled like baby powder.
~