A problem is when a poorly performing employee isn't fired (or disciplined) .... it doesn't matter if it's because of family/friend/contract/whatever.
If my offspring is performing poorly in a business I own, I might be inclined to give the yute more time and support and training to improve than I would a non-relative, knowing that my spawn will one day inherit the business and also wanting my grandkids provided for.
I don’t see that as a “problem” at all, since I consider my first duty to be to my family.