Hitler’s Family: In the Shadow of the Dictator is a 2006 documentary by German public broadcaster ZDF which asserts that Hitler exerted substantial effort into hushing up his family heritage for fear that ragtag bunch of ancestors and some of his then-living relatives would tarnish his image, or even expose the fact that his ethnic background was not 100% Aryan.
His family had a history of psychiatric disorders which he didn’t want to become public knowledge, and his second cousin was institutionalized in an insane asylum for nine years before being sent to the gas chambers by Hitler’s government for his disorder. His own father was born out of wedlock, and his mother was first cousin to his father (making Hitler the result of a limited gene pool).
He was also embarrassed by his own sister, Paula, and made her adopt a new name so that he wouldn’t be associated with her. That same sister would later become engaged to Dr Erwin Jekelius, a doctor who would later send hundreds of mentally ill patients to the gas chambers. The documentary makes use of authentic film footage of interviews with some of his family members.