How to litter tray train an older cat

[VivaLeBeaver]

Cat is 10yo and has always been an outdoor cat with a cat flap. We’ve now got a younger cat and even though it’s a dual scan microchip cat flap we’ve had to lock the cat flap as kitten was tailgating the older cat out.

Older cat still going out via the back door and can come in through the cat flap but she’s weeing in the house at night. So I moved a litter tray to where she was weeing but she now just wees by the side of the tray.

She hasn’t used a tray in ten years but she sees the kitten using the tray (we have two trays in total) so she must know what it’s for? And I’d have thought a tray would be more inviting than the carpet? She’s even now pooing on the carpet but at least the dog eats that! 🤷‍♀️🙈.

Only thing I can think is that it’s a covered tray....might an open one Make her more likely to use it?

Cant hurt to try an open tray. Might not like the litter either

Different litter is a good idea, thanks will try that as well.

Open tray, and try soil. You can gradually replace the soil with litter once she's reliably using it.

Yes to those ideas.

Is there any way you could shut a door between them overnight so the older cat has access to outdoors? Eg contain the kitten in the bathroom perhaps?

UTIs can cause cats to wee outside their trays because the cold of the floor provides relief, or something, but I agree it's not likely to be that.

Also the standard advice is one tray per cat plus one more, so I'd try adding the open tray rather than swapping them to start with, and make sure they are separate and not too close to the food. Can be difficult to achieve all of that in a typical house though!