BLACK SHEEP OF THE FAMILY
Meaning- The most unsuccessful or least admirable member.
Usage – He is the black sheep of the family always causing trouble.
Origin- This expression has been used at least since the early 1800s to describe a person who is a disgrace to a community or a family. Shepherds didn’t like rare black sheep since their fleece could not be dyed any colour and there weren’t enough of them to sell black wool.