They said "Bye, Bye, Bye" in 2005, but a source tells the new issue of Us Weekly (out Friday) that 'N Sync recently reunited in Orlando.

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Justin Timberlake, 30, joined former bandmates Lance Bass, 32, Joey Fatone, 34, and JC Chasez, 35, to celebrate Chris Kirkpatrick's 40th birthday at his Florida home. "Chris was surprised!" a source tells Us.

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For more on the boy band's surprise reunion, check out this week's Hot Stuff video, as explained by Us' Senior Editor Ian Drew and special guest Eli Lieb.

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Also in the roundup: Prince Harry behaves like an American commoner, new details on Nicole Scherzinger's split with racer Lewis Hamilton, Chloe Grace Moretz bonds with Dianna Agron, and much more!

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