(CNN) -- Adolf Hitler left no offspring when he died in his bunker in 1945. But he wasn't the last of the Hitler line. He had a nephew, William Patrick Hitler, who grew up in England, moved to America, and had three sons.
He sent a blackmail letter to Adolf, basically saying: If you don't give me a better job and treat me a little bit better, I'll go public with the speculation within the family that Hitler himself had a Jewish grandfather.
ZAHN: Whatever became of that threat?
It was a veiled threat that he would confirm the long-held rumour that Hitler's paternal grandfather was, in fact, a Jewish merchant, Leopold Frankenberger, who had had an affair with his grandmother, Maria, during her time in service to the family in Graz."