Sippenhaft is a German term referring to the idea that a family can share the responsibility for a crime or act committed by one of its members. The philosophy was applied to members of the military and the families of the conspirators involved in the July 1944 assassination plot against Hitler. Heinrich Himmler assumed responsibility for implementing the policy.
According to Himmler, this practice had existed among the ancient Teutons. "When they placed a family under the ban and declared it outlawed or when there was a blood feud in the family, they were utterly consistent.... This man has committed treason; his blood is bad; there is traitor's blood in him; that must be wiped out. And in the blood feud the entire clan was wiped out down to the last member. And so, too, will Count [Claus von] Stauffenberg's family be wiped out down to the last member."
Accordingly, the members of the family of Stauffenberg (the one who had planted the bomb that failed to kill Hitler) were all under suspicion. His wife, Nina Schenk Gräfin von Stauffenberg, was sent to Ravensbrück concentration camp (she survived and lived until 2006). His brother Alexander, who knew nothing of the plot -- and was serving with the Wehrmacht in Greece -- was also sent to a concentration camp. Similar punishments were meted out to the relatives of Carl Goerdeler, Henning von Tresckow, Adam von Trott zu Solz and many other conspirators. Erwin Rommel opted to commit suicide rather than be tried for his suspected role in the plot, in part because he knew that his wife and children would suffer well before his own all-but-certain conviction and execution.