Though Blake Lively turned 21 a few weeks ago, she finally got a chance to celebrate Saturday night with a raucous bash at the Palace Hotel — appropriate, since so much of her hit series “Gossip Girl” is filmed there.

Guests including her family, cast members and various fashion publicists were asked to dress in Twenties-themed attire, Lively herself chose Ralph Lauren.

This story first appeared in the September 8, 2008 issue of WWD.  Subscribe Today.

At midnight, a video played showing home movies of the actress as a young girl, lip-synching to hits like “I Will Survive” and “Come to My Window.” But rather than re-live the old days by having Lively sing a tune, Michael Buble took the mic at the end of the night and serenaded her with “Happy Birthday.”

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