To get back (way back) to the original subject at hand: I just read some reserach about parental investment in children from the 1970s to 2009 or so. While the study authors do make a bit of a fuss about--oh, look, look, wealthy parents are spending proportionally more and LOOK, the rich-poor achievement gap has widened at the same time this has happened, I will again note that this is HIGHLY SPECULATIVE. They're just noting two things that have happened at the same time. So what? We all know about that kind of error.

Furthermore, this particular paper shows that wealthy parents are spending more on early childhood care (daycare) and higher education (college)--AND they are forking over more money to their ADULT children. Yes. You read me right. The wealthy parents who are making their kids so fantastically successful? They're giving their 20-somethings money. Not my personal metric of success. Meanwhile, spending in the 6-12 age range was fairly low. So, basically, daycare and college are expensive, and rich people spend even more on these things. Not surprising.

http://link.springer.com/article/10.1007%2Fs13524-012-0146-4 (paywall, probably)

This isn't the paper cited in the NYT piece, but it uses a big dataset.