Risks of developing mental health problems if brother or sister affected

What is the risk of developing a mental disorder if a brother or sister has the condition? Now a large survey using data from all patients hospitalized in psychiatric wards in Israel, and their siblings, has given some answers: having a sibling with schizophrenia increases your risk of developing the condition by a factor of x10, with increased risks of developing bipolar disorder and other mental disorders.  Similar increases are seen with siblings of patients with bipolar disorder.