He catches himself remarkably quickly. That's appreciable, but it goes to show that there's somethin' more than the fiddling anxiety he's come to associate with Carlisle going on here. If he were in the guessing mood, something along the lines of a genuine hurt.

"Pal, if I took everything like that personally, I'd be dust by now." Brot finishes the meat Sans has on hand, once again eyeing Carlisle with sustained interest. He scritches at the fox behind the ears to get him to stay put, at least for the time being.

"You two were close."

It isn't a question; much more an invitation for him to continue, should he prefer.