The fact that his lips are still all puffy because he’s so sleepy, or his cool little skull and crossbone socks. I really do love those socks, so much so, I took a close up of them. 
No, I changed my mind again. It’s the I’m not completely awake puffy lips. Both my boys have them. You could always tell whether nap time was approaching from their lips. Whining and crying was occasionally a tip-off, but I’m going to try to remember the sweet signs.
