2.09 "There Might be Blood"

Serena invites Aaron to be her guest at a charity gala honoring Lily and Bart, but after discovering a secret that Aaron has been keeping from her, Serena begins to question whether Aaron is the guy she thought he was. Hoping it will help her chances of getting into Yale, Blair naively agrees to babysit the 15-year-old daughter of a prominent Yale donor. But the teenager, Emma, proves to be more than a handful and Blair begins to suspect that the evening may actually wind up hurting her chances of getting into the college of her dreams. So, Blair forces Serena and Chuck to help her find the trouble making teen when she takes off. Meanwhile, Vanessa discovers the relationship between Nate and Jenny, in which Jenny is planning with Agnes a guerrilla fashion show by crashing Lily and Bart's gala with th hope that it will either launch Jenny's career or ruin her chances of ever being accepted by the industry. Dan angrily tells Nate to move out of the apartment, while Rufus tries to deal with the rebellious Jenny.