my son is is 1 year and six months old he doesn't say muma or papa but listens to everything we tell him.

A. If the child is learning and understanding and responding then there is no problem as of now the child is not speaking then you should try and communicate more and more with the child as a child is generally in a stage where the child can pick up its speech is between the age of 9 to 2.5 years so you should actually wait till that age if you do not see that happening then you can consult the therapist but as of now you should try and communicate more and more with your child without any time