Arent we all immigrants?

So today is the major day for Mexican protestors, to demand their rights...
I'm completely confused on the issue, it just seems to me there would be a happy medium, but I'm probably wrong. Mexico depends on America's cash to support their economy. When workers are here they send hundreds and thousands of dollars back to their family in Mexico. In the long run, that works out to be billions of dollars that Mexico basis their economy on. Having a daughter who is part Mexican, I start to wonder who really have rights?
If I was not a citizen what would I do? Would I give up everything to make a better life in America? It's of course easy to say what we would do, since we truly are not living the life they have. I might very easily do anything to get across to a country that promised paved roads, jobs, food, education, clothing, medical, shelter and warmth for my family instead of being in a poverty stricken country, where all of those above are extremly hard to come by.