My husband, Peter, told me about the unlikely friendship. When we stay in Mexico, Peter walks the same route up to the environmental preserve every day. It’s a steep climb to the park, which is filled with wildlife and rare plants. Because Peter walks the same streets daily, he has gotten to know a lot of the people who have homes on the way up. The whole thing started with Reacher, an exuberant 75-pound Belgian Malinois, and his American expat owner, Anita. The Belgian Malinois is a dog often trained for search and rescue. You might have seen videos of them scaling walls. Peter never saw Reacher actually climbing any walls, but he never doubted his ability to do so if the need arose.