Self Soothing

I was rocking Pranav on my lap. He was half asleep and his eyes, half closed. As I rocked, he started to chant "aaa aaa aaa aaa" in a sleepy voice, something he does when rocked. He also started to pat himself rhythmically on his chest. I've never patted him to sleep, so I don't know where he got that, but it sure is funny to see a baby pat himself to sleep that way!