Rihanna Celebrates Birthday, Chris Brown Attends

Pop princess Rihanna celebrated her 24th birthday at a private party in Beverly Hills that Chris Brown reportedly attended Monday night.

About 100 friends and family members gathered at the Caribbean-themed party. Confirmed guests included Rihanna's best friend and singer Katy Perry, Bruno Mars, Kelly Rowland, and Coldplay's Chris Martin, among many others.

Surprisingly, reports indicate that Rihanna's ex-boyfriend with whom she experienced physical abuse, Chris Brown, was present at the party.

While her actual birthday is Feb. 20, the singer enjoyed Sprinkles cupcakes decorated with her native Barbadian flag, according to People magazine.

A professional deejay played music during the event, but the party also featured a bass drum player who performed Caribbean beats.

"Rihanna was dancing all night and had an amazing time celebrating with her friends," one partygoer told the magazine.

Rihanna's friends and family had the chance to get their picture taken in a photo booth at the party as well, where dress-up clothes were set up for guests to enjoy.

Toward the end of the night, a custom-made birthday cake was presented to the "Only Girl In the World" singer, whose guests then toasted her using more than 20 bottles of Armand de Brignac Brut Gold Champagne.

Party goers also took home pricey Camacho cigars at the end of the night.

The relationship between Rihanna and Chris Brown has been the center of many media outlets' focus in recent weeks, with rumors swirling that the pair are back together.

In 2009, Rihanna filed charges against Brown, who is well known for fits of anger. Later that year Brown pled guilty to the felony assault and received five years probation, as well as an order to stay away from Rihanna.

Likely in light of the recent rumors about her love life, Rihanna posted on her Twitter account Wednesday: "Its all about mastering the skill of ignoring ignorance! #1love."

Rihanna, who is referred to by friends and family as her real name, Robyn, released her sixth album titled "Talk That Talk" late last year. She remains a very successful pop singer in her own right.