regarding the kids, it's mostly not their fault, and some kind of humanitarian rather than economic logic may be appropriate.
but if you live far away please don't expect catholic and conservative south texas hispanics to vote for libertarian immigration policies. that makes no economic sense to them. they have the papers; they have preferred status and they want to maintain it. it's not about race and you'll find little to no racial solidarity between mexican nationals and mexican-americans. they will tend to aggressively compete with each other for scarce resources.