Originally Posted by Blackcat31:
Oh my goodness! I don't know how I missed this post but I have this same kid! Only the one I have is 2.5 yrs old.
Child is super mellow here and spends most of the day completely silent. Child will do what is asked of them. ie pick up toys, go sit over there, come here etc but says nothing. Not a single word. If asked a yes/no question I get a whispered yes or no or a head shake in reply but no actual audible words.
When we have group activities, the child happily participates but without sounds/words or expression.
Isn't necessarily shy, scared or over stimulated...at least not in any way that I've noticed.
But at pick up when mom or dad walks in, child makes a complete about face! Chats like crazy, sings, answers mom/dad, smiles, kisses them, says "missed you!" etc... 100% totally different kid. NOT the child I have in care.
Strange thing is the child isn't new here.
Been here since age 13 months.
So I don't really have any advice but am in the same boat.
I've learned that people are weird but kids are weirder sometimes. *sigh* 
She won't participate non verbally either at circle time. Or at least very rarely does. But she is the same as the child you have. Mom will come and she will say every child's name etc and words I didn't even know she knew how to say. She is not hard of hearing because she hears the door open for someone coming in my house and runs right there and says hi before she even knows who it is. I have tried changing the way I ask her things and still nothing. Mom said she usually talks around other kids so she doesn't know why she won't here. I only have 5 to 6 kids at most when she's here. But even on a day it's just her ( just this week Tuesday it was just her along with my own kids) she still didn't talk. She will do some sign language but that's even a struggle most of the time. I've thought of selective mutism but she seems too young for a diagnosis of that yet. She is also one that just started when I ask her to do something too. Even though she sees the other kids doing what I asked her to do. She's such a puzzle to me!