[He keeps quiet while Tony talks, not that he can get a word in edgeways, and he's rather surprised at himself that he doesn't immediately turn beet red at the question.. and the insinuation. The boy frowns, but in the interests of not disturbing Bruce, still keeps up the light twitching of his thumb behind the sleeping teenager's ear]

I wasn't about to say anything of the kind. Bruce is tired, and for some reason is unconsciously insisting on this. I happen to be fond enough of him to not pitch him onto the floor, so here we are.

[Arthur keeps his voice low, and glances back out of the window]

If this is going to be a problem for you, Stark, the door is just over there.