If anyone knows how to throw a birthday party, it's Jessica Alba. On Saturday, the Honest Company founder helped her husband, Cash Warren, ring in his 38th birthday with the ultimate pajama party in Beverly Hills. Guests included Shay Mitchell, Kourtney Kardashian, Joel Madden, Nicole Richie, and couple John Legend and Chrissy Teigen, who stole the show in matching KFC onesies. The bash also included a series of fun games, like beer pong and cornhole. While there were a couple of other stars who celebrated birthdays this weekend (Liam Hemsworth and Orlando Bloom), Cash's pajama bash definitely takes the cake.