Preschool 3-4 yrs old, mouths words, but no sound / voice

by Steffani
(College Station, TX)

I work at a preschool in the 3s class. We have this one boy that doesn't talk to us. When we ask him a question he will nod his head or mouth the answer with no sound. His behaviors don't seem shy as he plays and dances and does everything all the others do, but he won't talk. One day another child said, "Why doesn't he talk?".
I think he can talk and he can mouth word for us to read his lips, but he won't talk. He does talk some at home, but I think no too much.
My goal is to get this child to talk.
Any ideas....