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President Barack Obama's second Inauguration got off to an explosive start on Saturday when "Firework" singer Katy Perry hit the stage for the Kids' Inaugural Concert in Washington, D.C. Perry didn't bring any real fireworks with her, but she didn't need to -- her performance was spectacle enough.

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Showing off her patriotic spirit in a sexy stars-and-stripes-themed leotard, the pop icon sang several of her biggest hits, including "Teenage Dream," "Part of Me," "Wide Awake," and "Firework," which was accompanied by a slideshow of photos showing President Obama in action. First Lady Michelle Obama and her daughters, Malia, 14, and Sasha, 11, sat front row at the show and clapped and danced along to Perry's performance.

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"I'm very proud to be here," Perry said, "and to see the Obamas and the Bidens here for four more years!"

Earlier in the night, the crowd at the Washington Convention Center was treated to sets by Usher, Mindless Behavior, Far East Movement, and members of the cast of Glee. Usher -- clad in black leather pants, a matching jacket, and red sneakers -- kicked off the festivities with a high-energy performance of "Yeah!," followed by "Without You" and "OMG." 

Nick Cannon emceed the star-studded event, which honors America's military families and was streamed live to military bases around the country. But he got an assist from the First Lady.

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"Inauguration is a really big deal. There's balls. Everybody dresses up and dances," Mrs. Obama told the audience. "Let me tell you: I love every single minute of it. Every single minute. But I have to tell you that my very favorite part of this entire weekend is being right here with all of you."


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