Hot Celebrity Brothers: We Love Your Genes! (PHOTOS)

Mark and his older brother Donnie first rose to fame in the mid-’80s as two members of the boy band New Kids on the Block, though Mark dropped out almost immediately, eventually going on to form Marky Mark and the Funky Bunch. These days Mark busies himself with producing and acting in big-name films (without the Funky Bunch), and Donnie stars on the CBS series Blue Bloods... when not touring with NKOTBSB, the New Kids on the Block-Backstreet Boys supergroup.