Hi
@Garry,
As Bron says in the post above it could be that diabetic neuropathy (nerve damage due to high blood glucose levels) is making it harder for Elliot to use the litter tray. If neuropathy is affecting his legs then this can affect his mobility (getting in and out of the box) and also his ability to squat once in the box. It could also be making him feel pretty uncomfortable, poor boy (I have permanent neuropathy in my feet, and it's not a nice condition to have...) ...A litter box with lower sides may indeed be more accessible for him. And it could also be that the litter tray is too small for him to use at the moment, and he needs something with a bit more space in order to get his balance more easily. Some cats also struggle when the litter is too deep in the tray, as this can feel a bit unstable under their feet.
Neuropathy can also affect the digestive tract and the bladder. And this can mean that a kitty becomes less aware of their need to pee until late on, and they may not make it to the litter box. My first diabetic had this so badly at first that he sometimes peed in his sleep. He used to sleep on my pillow, and I woke up more than once to find my hair soaked in cat pee, and him still fast asleep beside my head...
This behaviour can be
very frustrating for us humans. But it's important to remind ourselves that our cats didn't choose to become diabetic, or to be stuck in high blood glucose levels. They would much rather be feeling happier and healthier, but that is not in their control. It 'may' be within
our control though...
...Are you testing Elliot's blood glucose at home? This usually makes it much easier to get control of the blood glucose. And if you are not yet testing are you willing to give it a try? It is not difficult to learn, but can take a bit of practice and patience. Many of us use ordinary glucose meters made for human diabetics. The test just involves taking a tiny weeny drop of blood from the edge of the cat's ear (or some people prefer to use the paw pads). This should not hurt the kitty. Doing this could really help you to help Elliot, and that in turn could considerably reduce the stress in your household...
I also second Bron's advice to get Elliot checked for urinary tract infection as this can cause inappropriate peeing. Cats in high blood glucose levels are much more prone to UTIs.
It 'may' also be that Elliot is avoiding the litter tray because he has come to associate it with pain or discomfort. When this happens cats may seek out alternative surfaces to pee on, and sometimes that will be soft comforting surfaces such as carpets, bedding, etc. ...In this case it can be a matter of breaking the cycle. This is something I had to do with my current diabetic kitty after she had a very stubborn UTI earlier this year that took a long time to resolve.
She took to peeing on soft rugs instead of using the litter tray. I cleaned the rugs with an enzyme solution to try to get rid of the pee smell (if cats can smell where they've peed they will likely use that spot again.) ...I also replaced the litter trays and tried a couple of different types of litter. She fairly soon went back to using the trays just as she had previously.
Really hoping that you can resolve this situation both for Elliot's sake and for the human household too.
Eliz