I was a veterinary technician for nearly 12 years. EVERY patient that lived well beyond their years was always unvaccinated or only for their initial puppy/kitten shots and then never came in unless they were sick. Funny thing is…they were rarely ever sick! Their visits were extremely minimal. I’ve seen a 16 year old German shepherd (insane) and one of the cat patients at a clinic I worked at was 26 years old!! The vet verified the age because she saw him as a kitten. She said they never vaccinate their cats and that client always had THE oldest cats she had ever seen! Makes you wonder.