Johann Nepomuk Hiedler
Legally , he was the stepuncle of Alois Schicklgruber ( later Alois Hitler ) , who was the stepson of his brother Johann Georg Hiedler , an itinerant miller who may in fact have been Alois' natural father . 
<triplet> Alois Schicklgruber <subj> Johann Georg Hiedler <obj> father