We have two cats, Laurel and Hardy, both males, neutered, and unhappy recipients of regular vet care whenever needed. Both are indoor only cats except on the rate occasion we let one or both of them out while we're with them in the back garden. Laurel is older, probably five or six years old now. Hardy is about three years old. We adopted Laurel from a shelter. First few years all was OK with Laurel; nothing to be concerned about really. Even when we adopted Hardy as a kitten, they warmed up to each other within a couple of weeks and have been fine with each other since then.
The issue is that Laurel has recently begun to spray in different parts of the house. We've observed this over the p

