If they want to live like sardines in a can, that's their choice. I prefer to live in a house with a little elbow room between me, the wife and the kids. And I can because it's a choice that I made because I have the education and the job that allows me to afford such a choice.
They got a family in some other country? Then get the fuck back there and support them. Can't cause there ain't no jobs, or too much corruption in the government, army and police force? Ain't my fuckin' problem - stop knocking up the wife with kids you can't afford to support. They don't like living in a room with strangers? Then go the fuck back home and live with their families. Problem solved.
It ain't my responsibility to make their lives easier when they broke the law to enter my country. Right now over 29% of the federal prison population in the USA are illegal immigrants. Stuff them in a C-5, fly them back to Mexico City, and dump them on the tarmac. Let them stay there and fix their own damn country.