Help! We have 2 kittens ( brother and sister) who are nearly 6 months old. They have been neutered recently. But they ( both of them) insist on weeing on our beds, the little buggers. They have a litter tray that they have access to but hardly use as they have access to outside most of the time. It seems to happen when it's raining heavily 
It's getting ridiculous; nearly every day if we forget to close the bedroom doors. We are a household with two young children and 3 dogs ( one is a 4 month old puppy) in case that's relevant.
I had to throw my very expensive king size duck down duvet out today. We can't go on like this. Any ideas?