I know there is really nothing I can do because it’s developmental, but my kiddo still wets the bed…

I know there is really nothing I can do because it’s developmental, but my kiddo still wets the bed at night. He is absolutely frustrated that he does despite me telling him he’s fine it’s just his brain isn’t ready yet. Well maybe that was a poor choice of words because now he says that his brain makes him dumb for wetting the bed. He has been refusing to wear his pull ups at night because he thinks he can train his brain. Well I’ve been washing bedding almost every night for a week. If it’s dry it’s because he isn’t really sleeping well enough because he doesn’t want to wet the bed. I’m not sure what to do next or what to tell him. 😔