I have never said it's impossible for a poor child to do well. What I said is that they won't get the same opportunities as richer people, and that that isn't fair on them.

Also there is no particular reason why upbringing duties have to be confined to biological parents. For example, in my family it would make a lot of sense for my sister to have children and for me to pay some or all of the school fees, because I don't particularly enjoy being around children and it would mean she didn't have to wait until her forties to afford to bring a child up properly.