Geraldine (W) and Gene (H) were married on December 20, 1958, and were divorced in August 1978. Custody of the couple's four children was given to W and provided for support payments by H for all four children. H and W have a minor son, for whom H is currently providing support. Another child, James (S), a party to this litigation, is mentally retarded. S was 20 years old, residing with his mother, unemployed, and not attending school. S' disability prevents him from securing employment. W first filed an action to modify the decree of dissolution to increase the support payments for the minor son and to require H to provide support for S. W filed a separate action for S. The trial court increased the support obligation for the minor son in the modification action, and awarded monthly support payments of $225 to S. H appealed.