Ah. stripy, quoting me on the first page. Yes I have said don't just look at how all the state schoolers do in their Oxbridge degrees. Look at people at aged 30 and 40 and their earnings and careers.
Of course it's only sexist families where women do more with children. Where real women are involved who often earn much more than men and are really good role models to children because they work full time and have balanced lives the father has as much contact with the children as the mother so the father's education matters as much as the mother's. The days of rich men marrying low IQ secretaries are over. All recent studies show people of similar education and income these days marry whether at the high income high IQ end of the scale or low down the scale.
If I am looking at what makes children do well (howeve ryou define that) first it is 50% genes. Marry the low IQ man with the good chest or woman and repent at leisure...and have probably have low IQ children (although two very bright people tend to have slightly less clever children because of how genetics work although not very much lower).
Secondly if we are talking about academic achievement at school if mothers earn a lot and pay 5 sets of school fees like I do/did then of course the child is likely to do well. Only 8% of children go to private schools but they make up 50% of good university entrants, 80% of judges etc etc. Nothing much a mother can do as good for her child as pick a very high paid career in fact and it's a load of fun too.
Thirdly, do what most of us do whose children do well - read to them every night, feed them good foods (not sugar), cuddle and love them, breast feeding (I expressed at work and fed all the children at least a year yet in the UK we have the worst breastfeeding rates in the EU and most women give up very very early on), as children get older let them read to you. Buy them a good peer group as teenagers so their role models are good whatever good to you means which might mean virginal religious girls who leave school at 15 to marry or it might mean top school in the country where girls go to Oxbridge or whatever is important to you.
Fourth relax. We are so laid back in this house. One of my teenagers told me tonight I'd said all he should aim for is slightly better GCSEs than his brother. I said well I would not object if you got all A*s by the way. You don't have to get as low results as you can get away with! Laughing as I type. Perhaps we are too laid back.