Off-on couple Rihanna and Chris Brown were photographed celebrating Christmas Day together at a basketball in Los Angeles. A source told UsMagazine.com the pair were \"laughing and chatting\" as they sat courtside at Tuesday afternoon\'s Los Angeles Lakers versus New York Knicks game at the Staples Center. Brown was placed on probation and ordered to complete community service after he pleaded guilty to beating Rihanna during a heated argument in a car in 2009. Despite their stormy past, rumors have been swirling in recent months that the recording stars have secretly rekindled their romance. Rihanna and Brown fueled the speculation when they released collaborative remixes of their respective songs \"Birthday Cake\" and \"Turn Up the Music,\" and tweeted Instagram photos of them together.