[Yeeeaaahhhh Katara. Well. That was a bridge Sokka would have to cross, wasn't it? He's glad when Zuko brings up Appa because that lets him just... kinda... ignore the subject of his sister. For now. Just for now!]

Because you told us. [Duh.] And when you first showed up, Appa licked you. It's kinda a dead give-away since, you know, usually he doesn't like guys who have thrown fireballs at him.

[[All the cool kids are doing it!]]