In Dos Rios, Texas, life is all about borders — and what happens when you cross the line.Nothing is simple in a border town like Dos Rios, in the Rio Grande Valley of Texas. Even for high school students Fabiola Garza and her younger sister Alexis, whose parents run a local Tex-Mex restaurant, Dos Rios is full of borders — where you should go, who your friends should be, which boy you should date.Dos Rios is also full of opportunities, but it's a town divided, between the haves and the have-nots, the Whites and the Mexicans-Americans, the Texans and the Mexicans, the legal and illegal. But through it all, the Garza sisters have each other. Water can be crossed, but blood is the ultimate borderline — no matter what.