Source: Amy Sussman/Craig Barritt Tamar Braxton may have just proved to everyone that she is, in fact, her brother-in-law's keeper as she popped up to support Birdman at the Cash Money/No Limit Records VERZUZ in Las Vegas while Toni Braxton was away. On the heels of an explosive episode of The Braxtons in which her sister Towanda accuses her of sleeping with Toni's men in the past, Tamar decided to take her sister-in-law duties to the max by coming onto the stage during Birdman's performance and wiping the sweat from his forehead.