Barnett, M. A. (1986). Sex bias in the helping behavior presented in children's picture books. Journal of Genetic Psychology, 147(3), 343-351.

The purpose of the present study was to determine whether male and female story characters in children's picture books are depicted as helping boy and girl story characters at different rates and in different ways. Males were found to be represented more frequently than females both as child helpers and as the recipients of help. Although the helping acts in the books reviewed were generally rated as more instrumental than expressive, the helping acts of female "nonhuman" characters tended to be rated as more expressive than instrumental. The helping acts in which one girl character assisted another girl character received significantly lower ratings of instrumentality and expressiveness than did the helping acts involving the other three child-child dyads.