1) Who do kids belong to?
Look at the history and international attitudes to custody rights. In the last 100 years or so in the US this has changed from the father (the provider), to the mother (the nurturing caregiver) and now it is (themselves?) whatever is best for the child.
2) Do the poor have a more concave risk function?
They are not in a position to gamble on, say, an entrepreneurial enterprise, even if the expected value of return is positive. Even though these gambles would more likely than not lead them out of poverty, they rationally do not take the risk because even a small chance of failure would be devastating. This would be different if they had a safety net (family, friends, government policy) that enabled them to take the risk.