hmmm,,,,,
Good question and I wish I knew.
I do know there is a strong link with heredity.
Proven by the fact that Beans grandfather, uncle, aunt and father suffer from varying degrees of schizophrenia.
When she was born, We only knew about her grandfather but as her aunt and uncle and father got older into their early to mid 20's, well, symptoms started for them.

But that is just what happened with us.
I wonder if there is anyone with schizophrenia who chose to become parents. That is a good question Newtus.