Rihanna's birthday party was full of famous faces, but one was MIA: her bestie, Katy Perry.
A slew of stars such as Zac Efron, Ryan Phillippe, Jay-Z, Diddy and Snoop Dogg hit the private L.A. bash Sunday night, but Katy was too busy elsewhere.
Was she trying to get back at Rihanna for missing her wedding ?
Katy was busy kicking off her California Dreams tour in Portugal, but still sent RiRi some birthday love across the Twitterverse.
"happy birthday boo. Wish I could b there to blackout! Luv U!" Katy tweeted Sunday as Rihanna was partying after she performed at the All Star Game.
The birthday girl totally understood, replying back "bitch are u kidding? I missed ur WEDDING!! This is small stuff boo! #whenworkcalls".
Good to see all is well between two of our favorite fierce females!