TMZ.com: Christian Combs Calls 50 Cent a 'Senior Citizen' in Fiery Social Media Roast - CHRISTIAN COMBS OLD MAN 50 CENT'S JUST MAD MY DAD DATED HIS BABY MAMA!!! - Christian Combs isn't taking 50 Cent's recent online digs lying down ... he's hitting back at the "senior citizen" by bringing up his baby mama!