If Sam had been more on the ball, his brain might have added things up and realized that Gabriel was on the verge of going into heat. It might have explained things, though possibly not.

He crossed his arms, watching the way the muscles in Gabriel's arms shifted as he worked the dough and crusts. "Whereas the worst I have to deal with is my grandmother asking me when she's going to get great-grandchildren." Deanna Winchester had pretty much given up on Dean settling down, so she'd turned to Sam. "Not to mention the questions about why Jess and I broke up."

Of course Gabriel would have heard about Jess. She'd come to town with Sam last year, after all. Though it was possible that the break up wasn't general news yet.