You knew it was coming.
Best friends forever but frequent enemies ever since we've known them, the lovely Blair Waldorf and Serena van der Woodsen are totally feuding again.
Last episode's drama looks like nothing compared to what's to come in "The Grandfather, Part II." Neither girl is without fault ... or ready to back down.
We love them both, but if you're forced to take a side, who do you go with? We're curious to see where Gossip Girl fan opinion lies. Tell us below ...
Whose side are you on (if forced to pick)?