The research actually says the exact.opposite of what you claim it does, Orlux
"Significant policy decisions have been swayed by the misconception across party lines that children need both a mother and a father. Yet, there is almost no social science research to support this claim. One problem is that proponents of this view routinely ignore research on same-gender parents," said sociologist Timothy Biblarz of the USC College of Letters, Arts and Sciences.
Extending their prior work on gender and family, Biblarz and Judith Stacey of NYU analyzed relevant studies about parenting, including available research on single-mother and single-father households, gay male parents and lesbian parents. "That a child needs a male parent and a female parent is so taken for granted that people are uncritical," Stacey said.
In their analysis, the researchers found no evidence of gender-based parenting abilities, with the "partial exception of lactation," noting that very little about the gender of the parent has significance for children's psychological adjustment and social success.
As the researchers write: "The social science research that is routinely cited does not actually speak to the questions of whether or not children need both a mother and a father at home. Instead proponents generally cite research that compares [heterosexual two-parent] families with single parents, thus conflating the number with the gender of parents."
www.sciencedaily.com/releases/2010/01/100121135904.htm