Backstreet Boy Nick Carter Celebrates His 29th Birthday
01/27/2009 AT 03:35 PM EST
Donning an AC/DC vintage t-shirt on his newly svelte body, Carter celebrated downstairs at the Key Club in Hollywood Monday night. Backstreet buds Howie Dorough and A.J. McLean – taking a break from recording their upcoming album – even came by for a mini reunion to surprise their friend.
"They shut off all the lights and did a surprise for Nick downstairs early in the night," says an onlooker. "They all yelled surprise and they had cupcakes for him."
Little bro, Aaron, hung out with the birthday boy in the VIP section where guests, including former 'N Sync singer J.C. Chasez, enjoyed a tower of Sprinkles cupcakes and jammed to a live performance by the house band, Steel Panther.
"Nick was good. He and his friends were just laughing up a storm in their VIP booth," adds the source of the group.
The high note of the evening hit when the birthday boy jumped on stage for an impromptu performance.
"He sang 'Don't Stop Believin' by Journey like everyone does. The crowd was egging A.J. on to get up on stage but he wouldn't do it," says the source adding, Carter "looked like he had a great time."
Reporting by MARISA LAUDADIO and JESSICA HERNDON
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