My little man is noisy in everything he does, including dream! He does the biggest smiles I have ever seen, and I was so jealous of his dreams. Now I get them too which is really lovely. He chats in his sleep (coos), licks his lips and acts as if he is drinking, his eyes roll back and sometimes open. I also read that they are digesting everything they have learned so far, so the cries are probably reminisces from birth! It is lovely to watch, like another part of them, a secret part, that we only get to view from the outside.