This is not terribly surprising, but is interesting.
[Yale University's Ebonya] Washington analyzed the family composition of the 105th Congress (1997-98), as well as how the liberal National Organization for Women ranked each member based on their votes on 20 women's issues. The rating scale ranged from zero (consistently voted against the NOW position) to 100 (always voted in accord with NOW's position).Now, if we could just require that each congressperson have one gay child, one black child, and one child born into poverty we might be able to get some things done here.
She found that legislators with all daughters have NOW scores that are 12 points higher than those with all sons. Among those with three children, "each daughter is associated with an increase of nearly 3 points," Washington said.