In around 2002, an American nine-year-old named Demi-Lee Brennan lost her liver to a virus.  She received a transplant from a twelve-year-old only a day or two later, saving her life. For some reason, her body adopted the donor’s blood type as her own, changing it from O-negative to O-positive, as reported by the Sydney Morning Herald. Typically, organ transplant recipients require immunosuppressive drugs to prevent their bodies from rejecting new organs, as their bodies treat the life-saving additions as foreign invaders. But Brennan’s case was different. She not only adopted the donor’s blood type, but also his immune system. Hers is the only known case of such a phenomenon.

 Borrowed by Daheap from Now I Know; Dan Lewis