Well, the smile vanishes, but the expression that replaces it is unlikely to be much more comforting to Meg.

"Oh, I'm not interested in Castiel right now.

"Don't flatter yourself, little girl. There's nothing you could tell me about him I don't already know. I knew Castiel when your ancestors' ancestors' ancestors were still primordial sludge.

"No, the person I'm interested in here is you."