I've lived with cats since I was five years old (26 years now).
Bo is 15 now and he is very dear to my heart.
We're not entirely sure how it happened but he tore the meniscus in his knee a couple years ago and although he's still a happy old cat for the most part, it has severely limited his mobility and he has walked with a bad limp ever since.
It breaks my heart that we can't afford the surgery.