Thanks for your reply. The thought of it being the fact that she’s unspayed didn’t occur to me since she’s so young and he was neutered at a really young age (before we got him at 12 weeks). I thought maybe he just wasn’t used to being around other cats and so didn’t know to tone down his rough...
I just adopted a 9 week old female kitten about two weeks ago. I have an older male kitten who is 9 months old and have had him since he was 12 weeks. He’s been neutered since we got him, and has always been a very normal and nice cat, cuddling in the bed at night and overall being really sweet...