Thirty twins aged 5 to 7 years old were assessed by a child psychiatrist in their home environment, and their parents were also interviewed. Umbilical artery pH, an obstetrical index and social class all failed as predictors of the dysfunctions found in these children. On the other hand, correlations were found between disturbances in family relationships and certain presumably "environment-free" variables. It is recommended that in child psychiatric counselling and treatment of "at risk" children more importance be attached to family development.