Howard doesn't necessarily need to say anything; Tony's perceptive enough to see his parting words have nailed their mark.

A twinge of guilt makes it impossible for him to lock eyes with Howard when he presses past him. So he shrugs, crumples the empty potato chip bag in his hand, then slaps the other one on Barton's shoulder as he steps aside.

"Hey, nobody's stopping you. But take good care of the old man, huh? Don't forget this guy's from the stone age."