I wouldn't do that with my siblings, though I've had friends with different heritages that even kiss each other. (including a family that kisses each other on the mouth) But from what we've seen of the Gilberts... it's odd in that context. We don't see that level of physical affection in Jenna or John's interactions with them. I think that's why it feels so irregular.

A certain level of dirty-wrong has never stopped me, however (note: my fascination with the Salvatores), so I love them tooooo. *g*