Reese Witherspoon celebrated her 40th birthday over the weekend with quite the star studded affair, but there was one major thing that happened that now leaves me wishing I was Reese Witherspoon. 

I wonder if Keith Urban was an actual party guest who just picked up a guitar and crashed the stage, or if he was a surprise performer for the birthday girl. Either way, I'm jealous.

 

 

The Los Angeles party also included a private concert from Taylor Swift, and lots of celeb power. As you can tell Kate Hudson had a pretty fabulous time as well...