My sister has found a note she made to herself, when my mother said "speaking of black sheep" and told her stories of 3 people:
Her cousin Bill (born about 1901, so her mothers cousin, I think) had been arrested in Spain and held in protective custody, after singing the Red Flag in a Fascist area during the civil war. He then went to New York, where he survived having his throat cut in a fight, and spent the war years in the southern US, before returning to England with a metal plate in his throat. [Communism and associating with people who cut each others throats are equally shameful, I should think]
The second black sheep was the unmarried mother of a child that was adopted by another member of the family. By our standards, not a black sheep at all.
The third we are puzzled by: she married the supervisor of the packing department in Lewises (a big dept store in Liverpool, not a John Lewis store) this was a perfectly respectable place to work - renowned for looking after their employees. The packing department was a bit low, to be sure. Any liverpudlians who can enlighten me?