The results of our longitudinal study suggest that children may be most susceptible to family adversity in the first year of life and stressful life events in the first three years of life and that this adverse influence may be persistent. Indeed, earlier studies have shown that behavioral disturbances at age three are associated with psychopathology at age 21 (Caspi et al, 1996). Our study demonstrated that maternal psychopathology (anxiety / depression occurring in 20% of mothers), as experienced by boys and girls during the first postnatal year was a strong predictor of hyperactivity and conduct disturbances until at least the age of 7 years. This finding is in line with previous studies that have shown that children of depressed mothers have increased rates of antisocial behavior and depression (Burke, 2003) and are often exposed to harsh discipline and poor nurturing (Caspi et al, 2004; Kim-Cohen et al, 2005; McLearn et al, 2006). Moreover our study showed that social deprivation had the strongest impact in both sexes when experienced from pre-birth to age one. Nevertheless, another ALSPAC study suggests that
