Among homicide offenders with psychotic disorders (MMD), persons having antisocial personality disorder (APD) with Substance use disorders (SUD), named here triple disorder (MMD+APD+SUD), are a particular risk group for severe violence. They accounted for 47% of a representative sample of this population. Pure dual disorder (SUD+MMD without APD) differed from triple disorder, and may not increase the risk of homicide more than MMD alone. Prevention of severe violence among persons with schizophrenia necessitates that effective therapies should be developed for persons with triple disorder. It was possible to estimate quantitatively the risk for becoming violent offender among a nationally comprehensive population of children and parents of homicide recidivists. An increased risk of crime compared to controls was transmitted across three generations, but violent crime only from homicide recidivists to their children. Support for families of violent offenders since early pregnancy with e.g. substance abuse treatments, contact persons and safe environments, may improve the life of several generations.