Do you have any siblings, parents or (other) relatives with SZ or BP (or schizoaffective disorder)?

If you do, do they have the same diagnosis or a different one (or should they, probably, have)? Do you have a borderline personality?

I'm trying to ascertain whether BPD, BP-I or BP-II has different predictive value as to (blood) relatives, siblings, parents.

It might be more interesting than you think. SZ tends to be more isolated than BP, for example, and BPD might be more likely in combination with SZ (even if one doesn't also have BP).

BP-II might occur in greater isolation than BP-I. And BP-I might occur more together with SZ. Those two things are less surprising.

What's also interesting is whether BP predisposes one to marry into a family where some might have BP, SZ or BPD, in whatever way or for whatever reason.