Children raised in a non-dysfunctional two parent household (regardless of parental gender / sexual orientation) witness healthy interdependence, cooperation, negotiation, trust, respect, conflict resolution, love etc. between their primary caregivers during their critical development period. Raising a child with a good partner is about more than resource availability.
Having both genders is really valuable, by providing role modelling and interaction with the neuro-diversity of both genders.
Of course these days some people think the genders are not different, or whatever, some people think every strange though under the sun. I'm not speaking to those people they can believe whatever they want.
Have a read of 'Families and how survive them' for some detailed analysis of the roles of both genders in childrens development at various stages in their life.
