Hi I have 2 year old baby ,activity wise he is good .but he is not reacting when we ask to do something.he play with toys and other kids,eating food by his own, give response when called by his name.some time he reacts some time not.is there any issue with his development ,he not even started mama papa etc ?, other kids of his age start responding to all other activity like pasing the things when ask ,answering nose ear questions but my baby is bot doing all these activity..he do whatever he wants to do.whom to consult please suggest