Except that is completely untrue. Every family I have ever encountered is split and bifurcated and generally not that reliable. True they exist, but by and large families are not that reliable.

I'm a father of three and have studied parenting outcomes for a while now. My children's outcomes in life are marginally related to how available I am as a parent beyond a certain minimal threshold - more important are socioeconomic factors. Even if you take that into account, even the most perfectly raised children (Whatever that means) have a high chance of winding up in an outcome that is less than optimal based on parental expectations - assuming that you have some aspirational expectations to begin with for them.

All that is to say that raising kids is a crap shoot and outcomes, either for you or for them, do not necessarily correlate with effort spent. Again, caveat this with "beyond a certain point" which is the bar of not living in poverty - arguably one major benefit of being successful in business.