[Sam shrugs, having expected the response. And honestly, he had faith that Dean would at the very least not go trying to kill the kid — especially not if the other Sam had asked him. Even if they're not the exact same people as those they share names and faces with, it's hard to deny there's a sense of obligation to them.

Well, for Sam, anyway. Sue him, he's a bleeding heart.]

... You know how this place works. You know we might not have any choice, in Lucifer finding out. It might not even be a matter of if, but when. If the town interrupts, and there's even just a crack in that door that I can't...

[He runs a hand down his face, looking - unsurprisingly - exhausted.]

I don't bite now either, you know.

[The implication's there:

But I could bite. I could be a bigger threat than the kid.

Dean's protecting Sam, but who is protecting them from Sam?

It's a real concern, in Sam's eyes.]

Just... try to let the kid down gently — a little sympathy for the devil's kids.

... Our dad was a patron saint of fatherhood in comparison.