Chris Brown and Rihanna are back together, musically speaking.
Two songs featuring the singers hit the Internet on Monday. Brown is singing on the remix of Rihanna's track Birthday Cake, and she's on the remix of his upbeat tune Turn Up the Music."
Brown admitted assaulting then-girlfriend Rihanna at a pre-Grammy Awards party in 2009. He's serving five years of probation for the felony attack. He made his return to the Grammys this year, performing twice and winning best R&B album.