Andrew's head snaps up, staring past Sam at the figure he didn't see approaching. For a frantic second he's trying to remember what he just said, trying to figure out how much Dean overheard --

And it's not even, he realizes, like they were discussing anything either of them needs to keep secret. There's just something about Dean's tone, something about the look on his face, that makes Andrew feel like they've just been caught at something.

(The look on his own face, he realizes a moment later, probably isn't helping that impression.)