You have a massive job ahead of you. My guess is that at least one of them has a urinary tract infection and that is what started this whole thing. Either that or there is a huge stress factor going on in the house that they can't deal with. They definitely need to be vet checked to rule out infection. Next, you will have to confine them to one room so that you can get the urine out of the rest of the house. You need an enzymatic cleaner that is designed for pet urine such as Zero Odor (www.zeroodor.com). Once you have that done, you need to purchase a cat litter called Cat Attract - this will help enormously in getting everyone going back in the litter box. It has been treated to attract cats to use the box. You may also need to purchase a feliway plugin to help with this - it has phermones that tend to relax cats and help them do things the way they are expected to. You will probably need to keep them confined until everyone is using the box 100% of the time. If there is anyone you catch NOT using the box, you may have to crate them in a large queen cage with litter and food/water and retrain in there. It will be work - but you can get it under control. My best guess is that the older kitty may be the original problem starter. Start with that one to see who has the infection and go from there.
Good luck! Let me know how things go.
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Lori McLaughlin
Your veterinarian should ALWAYS be consulted first and foremost when your pet's welfare is at stake.
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