Welcome RuffledFeathers223![]()
Quite the conundrum you have here.
It does seem strange that your cat has suddenly decided she doesn't want to use her own litter box. Typically there is 'something' which has caused the change in behaviour. You seem like you know quite a bit about cats, as you took her to the vet already. It is also great to hear that she doesn't seem to have anything wrong medically. Did the veterinarian mention anything about what could have caused this? Or what you could try now?
There are two other causes that come to mind for me. Firstly, has something changed at home? Any other new pets, children, people staying at home, a change in routine, etc. Otherwise, I've heard that when cats have a bad or painful experience, that can lead to them changing their behaviours. For example, if she once had any constipation or a painful experience occur whilst using the litter box, she may have associated the fear and pain of that experience with the litter box.
Thinking about how to fix this though is a bit harder. Would you be able to move her original litter box somewhere else? Or possibly get a taller gate to try to stop her from being able to access where the ferrets are? I'm not sure about how to train her to use her old litter box again. I found this article which may be of some assistance. It is a wikihow article, but I think the points are still beneficial. The article says to make the old areas unappealing and to try troubleshooting ways of getting her to use her old tray again. Hopefully, you find some benefit out of it?
https://www.wikihow.com/Retrain-a-Ca...the-Litter-Box
Hopefully, someone else may comment with some ideas of their own Ruffled. Best of luck trying to get her to stop using the ferret's box. Worst case, could you make the litter box the ferrets use bigger? That way the cat won't make as much of a mess, and if she is comfortable then sharing with the ferrets she may decide to leave their rice alone?
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