Mick Jagger will soon become a great-grandfather for the first time ... but he's also becoming a regular ol' grandfather again, around the same time. Not only is his granddaughter, 21-year-old Assisi Jagger, expecting a baby; Assisi's mom, 42-year-old Jade Jagger, just revealed she's also pregnant, and six months along, the Daily Mail reports. "Happy to announce this granny is going to become a mummy," she wrote on Instagram today alongside a baby-bump photo. "Double whammy this year." Mick already has four grandchildren.