When the singer-actress hit the stage to accept the choice music group award for her band, Selena Gomez and the Scene, she was serenaded at Los Angeles's Gibson Amphitheatre with an audience rendition of "Happy Birthday."Pictures: The red carpet
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Gomez also received cupcakes topped with glowing sparklers for her to blow out.
"This is the best birthday present ever," Gomez said.
The Texas native sat in the front row next to her beau, Justin Bieber, who also picked up a couple of awards Sunday night, including choice male artist and choice male summer star.