Did mental illness in your family or your partner's family influence your decision to have children?

Without knowing what problems the brother has there’s no way for any of us to say.

Even knowing exactly what problems he has, about the most specific thing an expert could say is about like this: “Everyone is at small risk of producing mentally ill offspring. Your risk is slightly higher than average.”

It seems to me that an answer like that doesn’t really bring you much closer to knowing “What should I do?” How lucky do you feel and how much risk is too much risk? No way for us to know what you think of these things.

Or, depending on the illness, “as far as we know, your risk is not any higher than average”. Some illnesses have a strong genetic component, others don’t; some are known to need an external trigger. Nobody gets PTSD without something to get PTSD about.

Same here. Though my sister and brother’s children seem to be doing fine.

Mental illness played no part in my deciding not to have children.

I attribute that to sanity.