Judith Monarrez crumpled onto her kitchen floor and wept when the news arrived in an email: Gizmo, her pet dog missing for nine years, had been found alive. Monarrez was 28 and living with her parents in 2015 when Gizmo, then two years old, slipped past a faulty gate in the backyard of their home in Las Vegas. The decade that followed brought a lot of change. Monarrez, now 37, moved into her own home, earned a master’s degree in English, and began her teaching career in higher education. But throughout the years, Monarrez said, she had never stopped trying to find Gizmo. Now, she was climbing into her car to drive across town to meet Gizmo at an animal hospital. Monarrez was later told that a woman had found the 11-year-old dog and dropped him off at the vet, where they scanned his microchip, triggering the email notification that sent Monarrez to her knees, crying. Within hours of receiving that email on 17 July, Gizmo was back in his owner’s arms. Monarrez called it “a miracle”. “Hindsight is 20/20,” she said. “I’m so glad I registered his microchip.” Their reunion came at the same time a new Las Vegas city ordinance requiring pet owners to microchip their cats and dogs is scheduled to take effect, on 1 August. Monarrez said on Thursday that Gizmo’s first week back at home had brought mixed emotions. It was clear, she said, that the nine years they had spent apart had changed Gizmo, too. The 8lb chihuahua had grown afraid of shadows, heights and birds, and he now walked with a limp. Monarrez said both of his eyes were severely infected, and some of his teeth were missing. “Even though he looked so different, when I looked in his eyes I knew immediately it was Gizmo,” Monarrez said, recalling the moment they were reunited at the vet’s office. “And as soon as I said his name, he tilted his head and he didn’t stop staring at me.” While Monarrez and her parents can’t stop thinking about what Gizmo endured after he went missing, their focus now, she said, is on addressing his health issues and “showering him with all the love that we were holding on to for all those years”.