Several weeks ago in his playroom, Jack put his thumb in his mouth and laid down in my lap. I asked if he was tired and he sat up, smiled, and put his head back down. It was remarkably cute, so I had to ask him again. And he did it again. So there was the cue indicating it was nap time. Of course I thought it might be a fluke, but sure enough, we did our little routine. It consists of feeding for a few minutes in his room, then reading a book - currently either Quiet LOUD or I Like It When. Sometimes both. Then we say "nite nite" to things in his room and as I am putting him down, his left thumb goes right into his mouth. As he is lying there, we say "I love you" and I tell him I will see him in a couple hours (wishful thinking on my part as he usually naps for 1 - 1 hour 20 minutes). Then I leave and spy on him using our Motorola baby monitor. He's been showing that he's tired pretty consistently, so I was able to capture the cuteness on video.