There is a law in at least some ex-Yugoslav countries about mandatory responsibility to care for your parents. You are required to do it by law, or your parent can complain to social services about it. You can be held liable even for not visiting your parent enough etc. There are some conditions though, so it only applies if the parent doesn't have enough means to survive, or if it's completely ignored by the child, etc. However, if the child proves in the court of law, the parent didn't actually take care of the child at all, this responsibility can be waived.

That being said, this would probably end up in courts, which are infamously slow and ineffective in these new failed capitalist republics, so it's doubtful if its actually applicable in reality.