Audrina Patridge Celebrates Birthday - Where's Lauren Conrad?

According to Usweekly.com, Audrina flew in from Hawaii from shooting her first movie (Into the Blue 2) to Las Vegas to celebrate her 23rd birthday. Turns out Lauren was not there, not sure why? I guess we'll have to wait till the 4th season to see it all...

Click here for the full article and picture: Audrina Patridge Celebrates Birthday Without Lauren Conrad