Except it's Maria Isabel who leaves their baby Katherine Jasmine behind with Maria Isabel's aunt. I believe the author ended his book this way to show that the United States' efforts to stem the flow of immigration, both in terms of harm to humans and futility. “When we build 700 miles of fencing, we honestly don’t understand that kind of determination,” she said. Sonia Nazario also believes that mothers make mistakes, especially in the eyes of their children, when they leave them behind to give them a better life. She also believes that the best solution is to dedicate resources and policies to the goal of improving these conditions in the countries where all of these undocumented immigrants come from..