Well, Kit has excelled herself.
I thought I'd wash the sofa covers as she'd wee'd on them and of course, the cushions were soaked through and impossible to wash as they were filed with a fibre sort of material. So I threw those and ordered some foam. I washed the base of the sofa in biological powder and put tinfoil on there. Kit pulled it off and still used it as her litter tray!! I know the smell is still there and I've ordered some special cleaner but no way am I putting new cushions on there until she stops using them as her toilet!!!
I'm so cross but I know she's not doing it on purpose. The kitten is perfect but if he sees Kit going where she shouldn't, I'm sure he'll follow suit!