u/rainbowbutters3

My cat, female, spayed, nearly a year old, has peed on my bed/mattress for nearly 4 days straight. Sure we had a few accidents in the past but they were never as frequent as this. Her litterbox is completely clean and she has free range of the whole house but chooses to piss on 3 pillows, then the mattress. She noticed I’d get mad and swat her if she began to dig or squat on the mattress, so just now she pretended to loaf on it and piss so I wouldn’t get mad. I cannot send her outside, what do I do? She has a sister who has never peed on anything.