Summarize the section titled, The Walls.

"The Walls" is a brief section about the various border control measures in place along the US-Mexico border. In Chapter 4, Raul and Ernesto walked for days in the Texas desert. They became lost and were eventually picked up by border patrol. The twins were detained for two months while they waited to be transferred into the custody of their elder brother, Wilber Jr., who was living in California. In the brief section entitled "The Courthouse," readers see a group of unaccompanied minors appear in immigration court without legal representation. In Chapter 5, Ernesto and Raul received their court date, enrolled in school, and try to manage the trauma caused by their trip north.