Little Sister - Part 2 (Patreon)

A continuation of one of the earlier captions here, commissioned by an anonymous Patron. Picture property of ABDreams. 

Heidi looked up hopefully from the blocks she'd been listlessly stacking and knocking down for what felt like hours as, at last, she heard a car pull into the driveway. It felt like hours since Sarah had decreed she wasn't to get a change until she got home, and since then, the mess in her diaper had gotten quite cold, making it feel even more disgusting every time she had to move... And all the times she'd had to pee since then hadn't helped, either.

She'd felt truly infantile, sitting on the floor and playing in her full diaper, with no hope of getting a change until somebody else said it was time. At one point, she'd even gotten desperate enough to admit to Andrew, "I don't even like this stuff, I was just playing along! Can I please change?"

"Sure, you don't," he'd chuckled, patting her mushy bottom. "Big girls just poop their pants for fun." Heidi would have liked to point out that she'd only done that because he'd given her a suppository... But he was still holding the paddle.

Now, at last, Sarah was home from work... Or was she? Heidi squirmed, realizing that car could have been anyone. Both her and Sarah's parents were known to stop in from time to time, and her phone had been off in the other room since she'd put these ridiculous clothes on, so even if her mom had called or texted to warn her - which she sometimes had the courtesy to do, though not always - she wouldn't have known.

She was almost glad to see her housemate step through the door, though not for long. Sarah sniffed the air loudly, looking right at Heidi, crouched on the floor. "Uh-oh, did somebody have an accident?" Heidi blushed, despite knowing that Sarah had already been well aware of what she'd done. "Did you take good care of my baby sister?" she asked Andrew, dropping the plastic bag she was carrying on the table to wrap her arms around him and give him a big, long kiss, making it last long enough that Heidi felt certain it was a punishment for her, wiggling in her messy diaper, having spent most of the day - most of all her days since moving in - fantasizing about doing that.

"I did what I could," Andrew answered, once they finally separated for air. "I had to spank her..."

"I'm sure it was well deserved," Sarah smirked down at the other girl. "Now, will you be a dear and take care of that?" she nodded down at the bag she'd brought in. "I suppose I ought to change her so she doesn't get a rash. That would be quite humiliating, wouldn't it?"

Heidi blushed, the idea of getting a diaper rash at her age having never even occurred to her. She started to follow Sarah, but the other girl told her, "You wait here... I'll be back in a minute." When she returned, she had a large changing mat, and, to Heidi's dismay, a fresh diaper.

"Sarah..." Heidi whined around her pacifier, trying to decide how to get out of this without admitting too much about her motives for playing along with Andrew for so long. "Sarah, I don't need another diaper! I'm not a baby!"

"Oh, no?" Sarah pushed her down onto the changing mat, pressing her hand roughly to Heidi's lumpy diaper, before unsnapping her onesie and pulling it up over her head, leaving her in just a dirty diaper. "Look at you... Do you think you look like anything other than a baby?" Heidi was surprisingly upset as Sarah yanked out her pacifier. "Answer me, young lady... Do you really think you're a big girl, lying here in a poopy Pamper? I wear diapers every night, but I don't even mess myself. Only a real baby would do that, don't you think?"

"W-Well, I..." Heidi stammered, whimpering as Sarah untaped her diaper, pulling it open.

"And what a mess it is!" she waved her hand in front of her nose. "You really don't have any control, do you?"

"I-It's not my fault!" Heidi squealed, cheeks darkening as her housemate began wiping her clean. It was nice to finally be getting rid of the muck that felt like it had invaded every inch of her down there... She would have liked to handle it herself, though.

"Oh, no, of course not," Sarah shook her head. "Your mommy should have done a better job potty training you, huh? Well, sorry, but your big sister doesn't have time for that, so it's just going to have to wait... Don't worry, though, I have plenty of diapers for both of us - we won't run out, as long as your babysitters don't go overboard with your changes."

"B-Babysitters?" Heidi gasped, trying to find the strength to get up and run away as Sarah slid the used diaper out from under her now clean backside. It was still pink from her last spanking, and Andrew had made it quite clear that, if she was going to need punishing again, he'd use the paddle... And it wasn't like she was about to run out the door totally naked.

"Of course," Sarah pushed a fresh diaper under her. "I know you had fun playing with Andrew, but he has to work, just like me... Only babies like you get to do nothing but sit around and fill their diapers all day. That's basically all you've been doing, isn't it? Have you applied for a single job since you lost your last one?" Heidi didn't answer; she didn't have to. She almost wished she had the pacifier back in... "So, I've found some nice babysitters to look after you during the day."

"Sarah, I don't... I'm not..." Heidi protested, gulping as the new diaper was taped snugly into place, and Sarah sat her up just long enough to pull a shirt over her head, one that didn't even come close to reaching the top of the diaper, much less covering it.

"What?" Sarah asked. "You're not what? A baby?" She lifted the wrapped up diaper she'd just removed from the other girl. "This says differently, little girl..." She set it down, leaning over Heidi, pressing her hand to the diaper on her. "And I hope you liked it, because this is the only way you're going to be using the bathroom from now on... Andrew is putting locks on the bathroom doors right now; only he, I, and your babysitters are going to have keys, and none of us will be letting you in there. It's just as well... You never were any good at cleaning up after yourself. He's already taken your car keys, too, just in case you thought you could hop in there and go to some place with a bathroom.... Not that I think you'd want to. We're also locking away your big girl clothes. Whenever you're here, at home, your diaper is going to be fully visible, like this, unless you're in a onesie. When I or your babysitters decide to take you on a little field trip, we'll be choosing what you get to wear outside... So you'd better behave yourself."

Heidi looked down at herself anxiously, hardly able to even process the thought that she was going to be spending her days dressed like this from now on, not even allowed to go into the bathroom without permission... She couldn't let this happen, not even if it meant risking Sarah kicking her out for trying to steal her boyfriend. "Sarah, I-I have to tell you some..." 

Before she could finish, Sarah shoved the pacifier back into her mouth. "I think I've heard enough big girl talk out of you for the day," she said. "If you say one more thing that isn't baby babble, I'll have Andrew in here to spank you silly. Now, go throw this away." She indicated the old diaper, which Heidi, blushing, picked up reluctantly, heading for the nearest garbage can. "No, no," Sarah shook her head. "Out there... We don't want it stinking up the house."

Heidi gulped, seeing Sarah's finger pointing out to the end of the driveway, where the trash cans were already waiting for the garbage man the next morning. Sarah would probably take the bags out of the cans in the house later that night, anyway - she always did, no matter how little was actually in them - so Heidi was sure this was meant as a punishment, making her feel pretty sure the other girl knew what she'd been about to say before silencing her... She shuffled towards the door, glancing back, hoping Sarah would stop her, or say she was joking, before Heidi had to step outside, diaper fully visible, carrying her old, clearly used one... 

She never did.