A very revealing study that Dr. Warren Farrell mentioned in his book "Father and Son Reunion", which explores the positive effects of children growing up in households where fathers have primary custody, is titled "Advantages of Father Custody and Contact for the Psychological Well-Being of School-Age Children". The study reveals how the children they researched were more psychologically stable and that they even had a more positive opinion of the opposite sex parent(the mother). When mothers had primary custody the children had a more negative opinion of their opposite sex parent(the father). Quote:
"The major finding of the study was that across a variety of
assessments of psychological well-being (self-esteem, anxiety, depression, problem
behaviors), children (especially boys) did significantly better in the custody of their
fathers. Moreover, children in father custody had the advantage of maintaining a
more positive relationship with the nonresident parent, the mother."
The findings are also explored in more detail on pages 19 and 24