
This topic proved harder for me than I thought it might...
But, eventually, I settled on Canadian politician Tommy Douglas (1904-1986) who formed the first democratic socialist government in North America. He is best known as the father of universal health care. Back when such things were popular (2004), he was voted 'Greatest Canadian of All Time'.
You may know his grandson, the actor Kiefer Sutherland.
This stamp shows a portrait by Yousuf Karsh
for Sunday Stamps - father figures