Bad actors who benefited from the success of relatives

[Monster Jungle X-Ray]

Don Swayze shouldn't count, there is no star or talent in this family anywere!

Well regardless of what you think of Patrick Swayze's acting ability, there is no denying that he was successful, ergo Don riding his coattails.

As for the Sutherland family I think Keifer's half-brother Angus has benefitted more (or not depending upon your perspective given how wretched Lost Boys 2 was) from who his relatives are.