One thing most poor people want is to feel better about themselves. Generally, their job sucks (if they have one), their housing sucks (neighborhood), their bank account sucks, and many other things suck, but having kids for some people gives them hope for a better future, or at least a chance for their kids to have a better life than they had. Of course, every person believes this when they start out with each child. I just had my first, and it is truly an inspiring event, it really does make you think about other things than just yourself and your own life. It may give them fulfillment that they created something and brought it into the world that is all dependent on them.... and maybe this is part of the reason some (not all) poor people have kids........