Kate Millett, feminist author, NOW committee member and prominent feminist had a large hand in shaping patriarchy theory and using her definition of it to demonize households where men had authority. Take a look at how she describes "experiments" where people attempted to conceive children outside of the "patriarchal" family structure and how to her frustration these attempts usually failed:
"To insure that its crucial functions of reproduction and socialisation of the young take place only within its confines, the patriarchal family insists upon legitimacy. Bronislaw Malinowski describes this as "the principle of legitimacy" formulating it as an insistence that "no child should be brought into the world without a man - and one man at that - assuming the role of sociological father."
By this apparently consistent and universal prohibition (whose penalties vary by class and in accord with the expected operations of the double standard) patriarchy decrees that the status of both child and mother is primarily or ultimately dependent upon the male. And since it is not only his social status, but even his economic power upon which his dependents generally rely, the position of the masculine figure within the family - as without - is materially, as well as ideologically, extremely strong.
Although there is no biological reason why the two central functions of the family (socialisation and reproduction) need be inseparable from or even take place within it, revolutionary or utopian efforts to remove these functions from the family have been so frustrated, so beset by difficulties, that most experiments so far have involved a gradual return to tradition. This is strong evidence of how basic a form patriarchy is within all societies, and of how pervasive its effects upon family members."