"Other," with elaboration, for example.
The variation comes after the yes or no. For example, "yes, they were too strict," "yes, they were abusive," "yes, they were unfair to me, but not my siblings," "yes, all of the above."
Opposite answers for the no side. Or you can keep it as yes/no/other with elaboration. The idea is to capture as many possible variations of answers, or to capture a wide assortment of answers. You could rephrase the question to be more neutral, but I'm guessing that would defeat the point of your question.
Anyway, if you're interested, you could look up sampling theory and design for more detail.