In 1979, China implemented its one-child-per-family policy in order to control its burgeoning population. Subsequently, concern has been raised about the policy and its potentially negative effects on children. In the present study, we examined these presumed effects on 202 adolescents born before the policy went into effect, 290 preadolescents born during the period in which the policy was being implemented, and 239 children who were born after the policy went into effect. Measures of fear, anxiety, and depression were obtained. Contrary to our hypotheses, based on concerns raised by the one-child policy, children with siblings reported significantly higher levels of fear, anxiety, and depression than only children, regardless of when they were born. For depression, this effect was qualified by a sibling status x age interaction. Children with siblings born after the policy went into effect, or during its implementation, reported higher levels of depression than did only children; however, only children and children with siblings born before the policy went into effect did not differ significantly from one another. Sociocultural factors associated with these findings are explored.