I have 3 cats and a dog. I believe that the youngest and newest of my cats, Chi is urinating underneath our bookshelf in our foyer. I have tried spraying "NO" there and we have a litter box on each floor of our house, that we do our best to keep very clean. There seems to be no rhyme nor reason to his behavior it can happen in am and pm, wether the litter box was cleaned that day or not, and before and after he was neutered. We have never had problems with any of our other animals. Any help that you could give me would be great!