Don't worry about it. My 23 1/2 mo old son says a few words but not too many. Childern talk WHEN THEY ARE READY AND NOT ONE MINUTE SOONER..... Just keep taling to him and eventually hewill talk back. Remember he is taliking but you just do not know what he is saying!!! Good Luck!!
Dear Aunt,
In general, children demonstrate some babbling by the age of five or six months; they use their first words around the age of ten to twelve months; and they combine words at eighteen to twenty-four months. By the age of two years, many children (but not all by any means) have acquired more than two hundred words. If your nephew is otherwise developing in a normal way, there's no need for worry at this time. However, he's now at an age when speech should be blossoming, and it's to be expected that he'll show some progress over the coming months. If not, it would be reasonable to be concerned.
If the only worry is in relation to speech/language, evaluation should be done by a qualified Speech & Language Pathologist/Therapist.