Christina Aguilera and the Jonas Brothers popped by Los Angeles’ Viper Room to celebrate celebrity blogger Perez Hilton‘s 31st birthday Saturday.
Aguilera performed “Lady Marmalade” and a sultry “Happy Birthday (dear Perezident),” while the Jo Bros presented Perez with a cake, autographed guitar and second Happy Birthday song.
Also in attendance were Kim Kardashian, Paris Hilton, Amanda Bynes, Meghan McCain, Heidi Montag, Spencer Pratt and Aubrey O’Day.