Child abuse of one of a pair of twins in Japan.

A nationwide survey in Japan on child abuse and neglect revealed that 10% of the victims were products of multiple births. None of the victims who were singletons had multiple-birth siblings, and only in a few cases were both twins abused. The findings indicated that one rather than both of a pair of twins was likely to be abused in Japan. Abuse of both twins was likely when there were serious parental or family problems, whereas abuse of one twin was associated with the child's medical problems or non-home care. There was no instance of abuse of a pair of twins when both were handicapped. Comparisons of the abused twin with the non-abused co-twin and examination of the abuser's attitude to the victim suggested that the difference between twins in their development or in their response to parents increased the stress of child-rearing and encouraged favouritism, which resulted in abuse of only one twin. Comparison by parents of children with their siblings may be a common factor in general child abuse because it is a natural thing for parents to do.