This idea came out of the thread for bad actors who rode the coattails of famous relatives. How many celebrities have relatives who managed to become well-known for some reason other than a successful relative?
I can think of two right off the bat.
Dr. Ann Cavoukian, renowned expert on privacy issues. As Information and Privacy Commissioner for the Province of Ontario, she's on the news quite a bit, usually because of the work she does in developing policies regarding important things like public security cameras and adoption disclosure. Her famous relative might be tough to guess, because he doesn't perform under his last name, just his first - Raffi.
Another one is the late Erik Nielsen, brother of Leslie, who was a member of parliament in Canada for 30 years. During that time, he held cabinet postings with a number of ministries, and served as president of the Privy Council, leader of the Progressive Conservative Party and deputy prime minister.
Sorry for "OFF TOPIC".
There's a "Progressive Conservative Party" in Canada? Who was the founder? Monty Python?
At topic: How about Geraldine Chaplin?
How about singer Tim McGraw . . . son of former major league relief pitcher Tug McGraw (who died tragically of a brain tumor a few years ago).
The only one I can think of off hand is William Henry Pratt's (better known to us as Boris Karloff) older brother John Henry Pratt, who was knighted for his services to the Crown, something his younger brother never achieved, and thus became Sir John Henry Pratt. The older brother not only was knighted for his services to the Crown, but had a long and distinguished career as a British diplomat.
Bernard Vonnegut, older brother of novelist Kurt Vonnegut, was a meteorologist credited with discovering the process of cloud seeding with silver iodine to produce rain.
According to Wikipedia he accumulated 28 patents during his career.