Devons usually seem to be a long-lived breed. The breeder I got my two Devons from had a female at the time that was 19 years old, according to her registration papers, yet was still in good health. My current Devon is 13, and is also in very good health and doesn't look like most 13-year-old cats. My first one, though, only lived to be 12. He was a blue-eyed white, and almost totally deaf, and many times there are health issues associated with that gene other than deafness. He had severe gluten allergies, and at that time, there were no gluten-free cat foods, so he was constantly at the vet's.