[A child with XYY syndrome as experienced by his mother. A report of daily journal recordings].

A mother's experiencing of the development of her son with "XYY syndrome" is presented based on notes from the mother's diary. According to recent findings in unselected longitudinal studies the boy clearly belonged to a subgroup of the more severely affected children. His developmental language and motor delays, other language problems and problems at school were typical, whereas his slightly reduced IQ, in the lower normal range, and aggressive and autistic symptoms were atypical. In many ways the mother's experience is comparable to that of parents of mentally retarded children. Complicating factors were the inconspicuous phenotype, late diagnosis and lack of professional help. It is shown that parental adaptation to a "handicapped" child can occur in phases. These can be understood through models of mourning or coping. It would be of great help to these families if self-help groups would be established.