Nazis Gassed Hitler's Cousin in Their Euthanasia Program

As part of the Nazis attempt to cleanse the Fatherland in order to create a superior race, the Nazis forcibly sterilized people they deemed unsuitable to procreate and killed others who had mental illness. It has recently been discovered that one of Hitler's relatives was one of those gassed as part of the Nazi's Euthanasia Program. This BBC article explains more.