I think one problem is that there isn't a real distinction between childhood poverty and poverty. There is no way to solve childhood poverty that doesn't also improve the parents' situation. As such, any solution to poverty then enables, for a certain segment of the population, a minimum level of poverty that they can choose to not fall below by having children.
Think about it like how the courts view jury nullification. They really don't like that the idea exists, but because it is a natural consequence of principles they follow concerning a jurors right to vote how they feel, they cannot stop it as long as the juror doesn't openly admit to it.
In the same way, a solution to childhood poverty has to be a solution to poverty for a portion of the population, and thus one has to accept a bias in which adult we solve poverty for or extend the solution to all adults, at which point we are now discussing general solutions to poverty.
You are talking about going above the baseline poverty level, but right now having a child is a strain (not just in poverty, but broadly across the working class as well), when that could at least be made inconsequential to your personal economic situation.
Think about it like how the courts view jury nullification. They really don't like that the idea exists, but because it is a natural consequence of principles they follow concerning a jurors right to vote how they feel, they cannot stop it as long as the juror doesn't openly admit to it.
In the same way, a solution to childhood poverty has to be a solution to poverty for a portion of the population, and thus one has to accept a bias in which adult we solve poverty for or extend the solution to all adults, at which point we are now discussing general solutions to poverty.