Perhaps it might help if you actually read the article I referred to?
Originally Posted by Taylor
How Does the Gender of Parents Matter? - Biblarz - 2010 - Journal of Marriage and Family - Wiley Online Library
"The entrenched conviction that children need both a mother and a father inflames culture wars over single motherhood, divorce, gay marriage, and gay parenting. Research to date, however, does not support this claim. Contrary to popular belief, studies have not shown that "compared to all other family forms, families headed by married, biological parents are best for children" (Popenoe, quoted in Center for Marriage and Family, p. 1).
More from the article:
"Studies of primary caretaker married fathers; egalitarian coparenting heterosexual couples; single mother or fathers after a death divorce or desertion; heterosexual single mothers by accident or choice; lesbian mothers and gay fathers after heterosexual divorce; planned lesbian motherhood through donor insemination (DI) or adoption; planned gay fatherhood through surrogacy or coparenting with women"
It's also not difficult to find research on adoptive parents, foster parents, kinship carers, grandparents, extended families etc
So basically your statement is just nonsense.