Season 1 - Episode 8

8 - Seventeen Candles
Although Blair is devastated by the state of her relationship with Nate, she manages to put on a happy face for her 17th birthday party and attempts to hide her feeling to her friends. Hoping to ease the tension between Serena and Vanessa, Dan takes Vanessa to Blair's party so the girls can bond together, but this ends up making Serena more uncomfortable, but then they found a common ground. Jenny brings her mom home as a surprise visit, but Rufus is not ready to forgive and forget.Also making it uncomfortable for Dan and Allison. Nate's parents ask him to make a huge sacrifice to save his father's business as he faces charges of embezzlement and fraud. Thinking that Nate is giving her a diamond necklace for her birthday, Blair couldn't have been any happier. Until, she finds out at the party, that Nate doesn't show up and the present turns out to be from Chuck.