There is(was) a possibility that his paternal grandfather was a wealthy Jew called Frankenberger or Frankenreither. Hitler's grandmother, Maria Anna Schicklgruber) may have been a domestic in this Jewish household in Graz, and it is possible that the son had got her pregnant. When Hitler's father (Alois) was about 5 years old, Maria Anna married Johann Nepomuk Hiedler. He subsequently did a bunk, and Alois was raised by Nepomuk's brother, Johann Georg Hiedler. Alois was baptised as Alois Schicklgruber, and legitimised in 1876 as Alois Hitler (illegally, apparently.)