Vince Vaughn helped former girlfriend Jennifer Aniston celebrate her 38th birthday at a star-studded party Saturday night (10FEB07). Aniston's best friend and former FRIENDS co-star Courteney Cox hosted the bash at her home in Beverly Hills. The star, whose birthday fell on Sunday (11FEB07), arrived at 7pm, followed a half hour later by ex-boyfriend Vaughn. The actor arrived with a male friend and quickly ducked inside the party, joining guests Sandra Oh, David Spade, Patricia Arquette and Kathy Najimy, but made an early exit, while Aniston stayed until 11:30 pm. The two began dating in the summer of 2005 while filming THE BREAK-UP and announced in December (06) they had officially split.