Paris Hilton turns 28 today and she celebrated her birthday at New York City’s Butter Restaurant on Monday (February 17). Butter owners Richie Akiva and Scott Sartiano organized the intimate dinner followed by a birthday celebration in the restaurant’s pink balloon-filled lounge downstairs. Lil’ sis Nicky Hilton, Mickey Rourke, Aubrey O’Day, Brandon Davis, JC Chasez, Tyrese, Chris Ivery (sans wife Ellen Pompeo), ex-boyfriend, Stavros Niarchos and The City’s Erin Lucas sang along to 50 Cent’s “In Da Club” birthday song as the starlet blew out the candles and sparklers of her three-tiered, hot pink cake (made by chef Alexandra Guarnaschelli). Happy birthday, Paris!!!