Re: CURSED families
I agree with KKF. Some examples could include the punishment given to the nations of any prior prophets, like Lut, Shuaib, Nooh (AS). Another possibility is that a nation can be involved in a punishment when sins become common among them. An example to this effect narrated in hadith is that they could be punished by having a tyrant ruling over them.
I’m not sure if this is still in the scope of your original question, but I do believe in effects of bad-dua and sihr (magic), both of which can have similar end results as the concept of a curse.