Perez Hilton's Birthday Bash

Perez Hilton arrives at his 31st Birthday Party in West Hollywood, Calif., on Saturday, March 28, 2009.

Kim Kardashian, right, Brittny Gastineau, center, and Lacey Schwimmer pose together at Perez Hilton's 31st birthday party in West Hollywood, Calif., on Saturday, March 28, 2009.

"Dancing with the Stars" partners Steve-O, right, and Lacey Schwimmer pose together as they arrive at Perez Hilton's 31st birthday party in West Hollywood, Calif., on Saturday, March 28, 2009.

"The Hills" couple Spencer Pratt, right, and Heidi Montag kiss for photographers at Perez Hilton's 31st birthday party in West Hollywood, Calif., on Saturday, March 28, 2009.

Meghan McCain, daughter of Sen. John McCain, arrives at Perez Hilton's birthday party in West Hollywood, Calif., on Saturday, March 28, 2009. The gossip blogger turned 31 this year.

Paris Hilton, left, and boyfriend Doug Reinhardt arrive at Perez Hilton's 31st birthday party in West Hollywood, Calif., on Saturday, March 28, 2009.

Emmy Rossum arrives at Perez Hilton's birthday party in West Hollywood, Calif., on Saturday, March 28, 2009.

Aubrey O'Day poses for photographers at Perez Hilton's 31st birthday party in West Hollywood, Calif., on Saturday, March 28, 2009. The gossip blogger turned 31 this year.

Ashley Tisdale arrives at Perez Hilton's 31st birthday party in West Hollywood, Calif., on Saturday, March 28, 2009.

Amanda Bynes poses for photographers at Perez Hilton's 31st birthday party in West Hollywood, Calif., on Saturday, March 28, 2009.

Tara Reid poses for photographers at Perez Hilton's 31st birthday party in West Hollywood, Calif., on Saturday, March 28, 2009.

Singer Christina Aguilera, third from left, and Perez Hilton, second from right, pose with backup dancers at Hilton's 31st birthday bash in West Hollywood, Calif. on Saturday, March 28, 2009. Aguilera surprised the blogger by singing a rendition of "Happy Birthday" at the party.