Two cohorts of boys were examined while attending a well-baby clinic and reexamined at the end of the first grade of elementary school. One cohort (n = 57) consisted of boys born in the year of the Six-Day War in 1967. The other cohort was born 2 years later (n = 63). Data on socio-demographic background, early development, behavior at school and at home were obtained from the mothers and the teachers. Statistical analysis showed that the "war children" had significant developmental delays and regressive, non-affiliative and dissocial behavior. The children, who were in their first half year of life at the time of the war, were much more disturbed than those of whom the mothers were pregnant at the time of the war. The findings suggest that a disturbed mother-child relationship existed in the former group.