With her pooch in tow, the Gossip Girl star celebrates her 21st b-day on the New York City set of her show. Plus: Ashlee Simpson, Lindsay Lohan, Paris Hilton and more

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Willy Wonka she's not: Madonna opens her Sticky & Sweet world tour in Cardiff, Wales, on Saturday with a commanding pose in knee-high leather boots and top hat – just one of her high-end costumes.

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