Are reborn (rebirthed?) Sims fundamentally broken?

I finally got around to having a sim be reborn. He got the burning soul trait, the whole shebang, and I started him again as a child. But it soon seemed something was wrong. He was back in the same house as before wth other children and a teen. The rest all fulfilled their needs perfectly, but he simply refused to use the toilet until it was absolutely necessary, the same with eating, didn't use anything fun, and showering was just plain not gonna happen. Mostly he just ran around chasing down other sims and obsessively chatting with them, and if no one was around, he just sat there doing nothing. I tried moving him in and out, into another house, same thing. I took out the other sims, same behavior. I even made another sim with the same basic traits and age, and he worked fine. But something is just wrong with him. I tried removing every reincarnation trait I could but still nothing. His autonomy is just somewhat off, even after aging up. Had anyone else had anything similar happen? Disappointing, for sure.