My 12 month old only makes noises when its quiet. He goes mute when I talk to him or repeat back his noises.

I know its a little early to be concerned but my oldest son had to be in speech therapy for a couple of years so I want to make sure I'm doing everything right.He has a pretty large understanding of 35+ words and phrases. Its crazy to me because I can teach him a word by saying it 2-3 times and he will remember it 2 days later. We play games like peek-a-boo, hide and seek and little other things like "Can I have one ball? Two balls? Three balls?" so I think he is developing great. But when I try and get him to speak, he goes silent. The one we work on the most often is 'Mama'. I'll pat his chest and say his name, then I pat my chest and say Mama. He smiles really big and enjoys doing it but makes absolutely no noise. He points to objects when he wants me to tell him what they are and acts thrilled after I say it.Its weird though because he doesn't laugh either.. The last time he giggled was around 5 months. If he finds something off the wall hilarious, he only lets out one little squeal.If he's babbling and I repeat back the noises, he stops. He won't start making noises again unless its been completely quiet for 5 minutes or more. I talk to him constantly, tell him what we're doing, the name of objects or sing him songs. Sometimes I wonder if I talk enough for the both of us. Maybe he just wants some peace and quiet? via /r/Parenting http://ift.tt/2cMzEkv