A breeze swept over me as I looked over Laguna del Carpintero in Tampico, Tamaulipas. Nearby, my three-year-old son Lucas and a local boy about the same age took turns rolling their miniature monster trucks down a blue playground slide. Lucas’ Hot Wheels rattled down first, then the other boy’s lime green truck. Off in the distance, my partner walked back with agua de jamaica from a street vendor. It was a moment of bliss that had otherwise evaded us that week. We left the U.S. on Jan.