The frequency of death certified as due to cerebral hemorrhage among the brothers and sisters of 180 index patients with a proved cerebral hemorrhage has been compared with its frequency in the population of the same age and sex at the same decennium of the century as given by the Registrar General. There was no statistically significant excess of death certified as due to cerebral hemorrhage except among the brothers of female index patients (p < 0.05). The significance of this finding is discussed.