He's relieved Misa is trying to be reassuring herself, he knows she's withdrawing for a reason. And he needs to address that. But for the moment, he can enjoy holding on to his son. Eventually, he may be able to hold Luke outside this suit, to feel his son's head against his shoulder. His son.

There is a part of him that doesn't want to sleep, just in case this is another dream. He's not sure he would want to survive, if it were.

Instead, he keeps a light feel on the pair of them, and rests - while also sensing the area around them. Just in case.