"Good morning Mummy!" I said with a laugh, as Mum came in to change my diaper. It was late in the morning, and I might just have decided to wet myself before waking, simply because I was too lazy to get out of bed. Today was theoretically a day of making sure that I had everything I needed for a new year of school, and catching up with anything that remained of my summer homework. But by long tradition, for me and nearly all my friends, the last day of summer was an excuse to be as lazy as physically possible and do nothing that was asked of us.
"You're still a little baby, then?" Mum asked. I could see that she was amused as well, but slightly more serious than me.
"It's the end of summer," I said. "I don't have to be a big girl until tomorrow."
"That might be true," she said. "But I think somebody needs to wake herself up a bit today. You can't go on having a soggy bum when you go back to school, can you? I think you should have a day being all grown-up, so that you can make sure you've not gotten into any bad habits during the weeks of your punishments. And also..." That was where she hesitated, and I knew there was something she was a little less certain about. I made a stab at guessing.
"You said Lindy had to be a baby still today," I said. "She doesn't get to grow up until she goes to school, meaning one less day of spending time with her friends. But I need a break?"
"Yes. And that's why. You see, this is supposed to be a punishment for her. For you, it was always half a game, which is why I had to let you believe that Hugo was upset before Lindy would realise that she'd crossed a line. But... even if this is a token punishment, I want her to feel it. I want her to suffer just a little to drive the point home. That means she can't go on teasing you the whole time. She needs a day, or half a day at least, where she can see that she's in a lower position. While you were both being "punished" with sandcastles and finger painting, she kept on teasing you the whole time, so it was kind of like she's still the big one. I think that to really make sure she understands what she did to you, she should have some time under your control. Which means you need to start acting grown-up before she is allowed to."
I nodded along as she was talking, and thought about my little sister. I guessed that I could still play with her, and we could still both have fun. Even if I was taking charge a little more, it could still be fun.
"Okay," I said a few seconds later. "Maybe I'd better still wear a pull-up today, just while I get used to being potty trained again. But I think I won't need it."
"Whatever you want, sweetie. Do you want me to put you in one and help you dress, before you're properly grown up?" I blushed, but there was no way I could say no to that, especially when she was grinning at me so widely. I let Mum keep on talking to me like I was a toddler, and raised and lowered my arms and legs as commanded while she put me in one of the pull-up diapers, loose jeans, and a Punk Snail hoodie. I wondered why she'd chosen that one; it was at least a year since I'd last worn it, and barely even listened to their music now. But when Mum stood me up and led me over to look at myself in the mirror, I understood. I was in a baggy hoodie with a fringe around the edge; meaning that it was perfectly suited to making it even less likely that the extra bulk of my diaper would be visible.
"Thank you!" I said, doing a twirl. And then I hugged Mum close, trying to show just how grateful I had been for this summer, before I stepped back and thanked her again, putting on a voice that didn't sound like a bouncy, over-excited toddler this time.
When I got down to breakfast, Lindy looked a little disappointed that she couldn't tease me. But she didn't fight; she knew that this was something she had brought on herself, and she had accepted the punishment as a way to remind her that she must never act like that again. I didn't think that she would be any trouble now; and some time today she would be allowed to act her age again. If she really wanted to, of course.
"Sally?" she said looking up. "I... I didn't say it properly before. I was kind of... worrying about how you were feeling. But I want to say it now. And I kind of want you to understand."
Mum put down a pacifier on the table; giving me the sign that Lindy was still my baby sister, and if she started stressing me out I was allowed to shut her up. But right now, I wanted to know what she had in mind. I nodded.
"Look, it's..." Lindy started. "I just... I want to say I'm sorry. Properly. I got this idea into my head, you know? That you were into all the adult baby, teen baby, all that type stuff. And even when I should have realised that it wasn't you, I had like this... this mental image, I guess you'd call it. I had this picture in my head that we're like big rivals, and the only way I could stop you doing that trick with the bowl of water while I was sleeping... I was so certain you were doing that, and it was lite the only way I could stop you was to turn it around on you.
"I know now that it's not true, but it's still easy to judge things in... like... that state of mind. When something new happens, I automatically think about it in the context of that stupid story that's been running around my head. It's pretty hard to shake. I know it's wrong, but even so... Have you ever had something like that? When there's like a mental image that's so persuasive, you try to fit every new thing you learn around it?"
"I think I can kind of get what you mean," I said. "But Mum did make it clear to you that I couldn't have been responsible. At least some of those nights. But like... when you see the proof, you still feel like it's some kind of trick, right? You see new evidence, you start thinking about how I could have faked it, and never consider that you could accept it as true."
"Right. And... Well, there's a reason for that. A reason I couldn't get that idea out of my head. It's embarrassing, I don't want to say. But I know what it was, and now I know where all those ideas came from... I promise I'll do better at drawing a line between reality and fiction."
"Fiction?"
"Okay, okay!" she said. "It was a book I was reading, okay? About this huge sibling rivalry where a kind of prank war keeps on escalating until it turns into like Bond villain levels of Machiavellian schemes. And the main character's got so many personality quirks and like little neuroses that I can identify with, it feels like I'm reading about myself. It crept into my dreams, and those dreams seemed so real, I think on a subconscious level I was thinking of myself as Sydney. But I finished that story now, and I can see how different it is from the real world. So I'm sorry; the paranoia she had kind of felt so real."
"It can be like that with really good books," I said, quietly. But I had to wonder how good an author had to be to get my sister to behave so far out of her usual character for so long. Was this just an excuse because she'd started to figure out how I really felt about the baby stuff? Or because she's actually been trying to get punished, and hadn't understood why Mum kept buying into her accusations? Either way, I wasn't going to push her anymore. The apology felt real, whether I believed the story she was telling or not.
"Thanks," she mumbled, and looked down at her hands again. "It's just... I didn't want to hurt you. It always just felt like an arms race, like you were being right to spite me or something. And I know how dumb that sounds. It kind of... When I say it like that, it makes me understand just how dumb I was not to see it sooner."
"Well, I'm sure you'll be more careful in future," Mum said cheerily. "And it's the last day of your punishment. If you're good today, maybe you can even change back to normal when I get home. But I do need to go out today, so for today... Sally's still your babysitter. Be good for her."
"Moooom!" Lindy moaned. "You don't need to..."
But Mum was already grabbing her coat and bag, and was gone before Lindy could think of any kind of coherent protest. She turned back towards me once had the house to ourselves, and I could see the pleading in her eyes.
"Look, I need to..." she started.
"Do you want to be punished?" I asked her. I knew that probably wasn't the best way to put it, but I hoped she would understand what I meant. "I'm sure I can think of–"
"No! I said I'm sorry, you don't have to keep on–"
"Okay then. Well, I don't have time to be looking after a baby today. I want to catch up with some friends before school starts again, so I'm going to be out most of the day. So I'll trust you to be a good baby, and only do things that you're allowed to do while I'm out. Okay?"
"Do I have to stay at home?"
"If you're a baby, I guess so," I said. "I'd better not see anything to suggest that you've been out with your friends when I get back. Understood?"
I'd finished my breakfast by then, and I was getting ready to go out as well. And as hard as it was to work out what was going through Lindy's head right then, I could guess that she would be going to visit her crush just as soon as I was out of sight. She was smiling as well, so whatever interest she had with being babied really hadn't carried on once we got back from the beach. I didn't need to understand her thoughts there, I just knew that she was glad to be free. And I was sure now that keeping up this punishment for one last day wasn't going to make any difference to her future attempts to bully me.
I hesitated before going out. Of course I was still wearing a diaper; and there was nobody to make me now. But while I had it on, there was no reason to change. Just wearing one didn't make me a baby, and like Mum had said, it was a sensible precaution when I'd had a week to get used to being able to go just about anywhere. I didn't think it was likely I'd have an accident, but... well...
Any excuse to hold onto the memories of this summer a little longer.