It depends on the culture. I’m sure that you are aware of the fact that in many cultures child rearing is considered “women’s work.” The nuclear family is a rather new development in the history of human civilization.
“Merriam-Webster dates the term back to 1947, while the Oxford English Dictionary has a reference to the term from 1925; thus it is relatively new.
-Wikipedia
To what do you attribute the current condition of blacks in the US, when you consider that before the advent of the welfare state, blacks we tracking whites in most markers, and some statistics show they had a lower illegitimacy rate than whites?
Or did I already provide the answer?