C Chaykin writes:
"Here's the grain of truth: Someone in the family changed their surname.
Not surprising, since many "last names" were, literally, "son of X," and
changed from generation to generation."
Surnames as we speak of them did not change from generation to
generation. The "son of" formulation is called a patronymic. All
European countries with a substantial Jewish population required fixed
surnames by 1861; most, far earlier.
Princeton, NJ USA