Rihanna Celebrates Her 23rd Birthday w/ Jay-z, Beyonce, Diddy - Katy Perry A No Show (PHOTOS)

Rihanna celebrated her 23rd Birthday at a Beverley hills party, inviting a whole host of A-list pals - including Beyonce, Jay-Z, P Diddy and even Zac Efron. Take a look inside...





Wondering where her Bestfriend Katy Perry is? Katy couldn't make it, she tweeted RiRi saying,

"happy birthday boo. Wish I could b there to blackout! Luv U!"

Rihanna hit her back with,

"bitch are u kidding? I missed ur WEDDING!! This is small stuff boo! #whenworkcalls".

lol