Backstreet Boys Singer Howie Dorough Expecting Baby No. 2

Us Weekly -- Howie Dorough had an extra reason to celebrate his 39th birthday!

On Aug. 20, the Backstreet Boys singer announced via Twitter that his wife, Leigh, is pregnant with their second son. "Thanks to family, friends and fans for all the amazing birthday wishes," Dorough wrote. "This year I'm receiving the best gift from my wife: another baby boy!"

The couple, who wed in December 2007, are already parents to a son, James Hoke, 3.

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"I know it's not until Wednesday, but I already feel like I am having an incredible birthday with the baby boy news and all of the amazing birthday wishes!" Dorough tweeted Aug. 20.

Two days later, on the boy band member's actual birthday, his son celebrated by singing "Happy Birthday."

"What else could I ask for?" Dorough tweeted. "These precious moments are what life is all worth living for."

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Dorough and his bandmates -- Brian Littrell, 37, A.J. McLean, 34, Nick Carter, 32, and Kevin Richardson, 40 -- are slated to perform Aug. 31 during the "Good Morning America" Summer Concert Series. It will be the band's first performance since Richardson rejoined the group.

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Dorough isn't the only Backstreet Boys member with a family to feed: Richardson is father to son Mason, 5, and Littrell is father to son Baylee, 10. McLean is currently expecting his first child, a baby girl, with his wife, Rochelle Karidis.

The Backstreet Boys are currently working on their eighth studio album, slated for a spring 2013 release.

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