S2E19 : The Grandfather

Devastated by the turn her life has taken, Blair opts for a wild lifestyle instead of her perfect Waldorf life, causing Chuck and Serena to become concerned. Vanessa tries to convince Nate that he needs to move on after his mother's family, the Vanderbilts, abandoned him and his mother. Trying to be honest with each other, Lily and Rufus both put together their lists of past relationships.