DSS 3yr,5mth old. He doesn't speak at an age appropriate level, you can understand occasional words but its mostly babble and everything begins with "d" Dish for fish, etc. He is only partly toilet trained (mostly because his mother didn't bother until recently) he doesn't seem to interact with kids other than his brother (at park just wants to swing, or climb trees rather than play with others), he doesn't know colours and doesn't ask all the "annoying" questions most pre-schoolers do.
His physical development/coordination etc seems fine but to me he seems cognitively delayed. Am I righto be concerned or should I ignore it? I have mentioned the speech and my partner agreed but was convinced by his ex that he was just shy around us so didn't speak, I tried to point out that he doesn't not talk, he just isn't understandable (like hes stuck at two).
Any advise appreciated