Don't want to pry but....austism???

[mum3girls]

I agree with all that Meg said, your description can still fit into the 'normal' range of development. A paediatrician would definitely be the person to see to get a diagnosis.

The hard thing is (on top of you not having a good relationship with your SIL), it's hard for some people to come to grips with the idea of having a special needs child. I know some people who have really stuggled with the idea, feeling that if their child is diagnosed with a special need that it's 'their fault', that they may be bad parents, and may feel that if they 'ignore the problem' it may go away IYKWIM?

Maybe someone who has a closer relationship with your SIL could subtly talk to her about everyone's concerns, and maybe try to get her to just speak to a GP (who would have to give a referral to a paed. anyway).

Good luck.