Sam puts him to bed, like he's the big brother. Dean'll let it slide this time. Sam hasn't been this off the rails in a long time, and Dean's pretty worried about how precariously he seems to be hanging on. It doesn't hurt anything to let Sam fuss.
He puts on pajamas, which is not something he ever does – that's Sam's thing, pajamas. But they make Sam comfortable and Sam's trying, so Dean goes with it. He'll probably strip them off in the middle of the night when he's two million degrees, but they are pretty soft and comfortable.
Climbing into bed accidentally reminds him that Sam actually clocked him a good one when his jaw brushes his shoulder. He's going to have one of those deep bruises that hurt but don't turn colors.
"Need anything?" Sam asks. "Water? Hot chocolate?"
Dean just shakes his head. Sleeping is the only respite he gets from Michael banging on the door; he'd sleep all day every day except the banging reminds him that Michael's there and Dean needs to keep a lid on it. It's the falling asleep that's the trouble. He remembers Sam being unable to sleep because of Lucifer, how bad it was, how broken he got. He hopes he doesn't get there, but he doubts he'll be that lucky.
"What is it?" Sam asks. Damn, the kid is just too perceptive.
Dean sighs. "Tough to fall asleep with Michael having a Macy's day parade inside my brain."
Sam nods like he knows, and it breaks Dean's heart to think about why. He kicks off his shoes and climbs onto the bed, pulling Dean against him. He starts humming. Going to California, which was one of Dean's favorite Zeppelin songs before Sammy actually went to California. Now it reminds him of Jess and all the lost potential of Sam Winchester, esquire.
It's soothing, though, and it drowns out Michael, so Dean puts his ear against Sam's chest and lets the sound of it lull him to sleep.