I got the follow image of Nishiko...
Nishi walks over to the litter tray and takes a sniff... "Ducking Hell! This is stinky, really stinky and so dirty. Mummy and Daddy need to clean this more often because I can't use this!"... Nishi gets so frustrated because of the pong from the dirty litter tray that she goes ahead and does the one thing that she thinks will tell Mummy and Daddy that she is unhappy... I the middle of the night she creeps into the bedroom and jumps on the bed. She squats... Mummy feels a wet puddle soaking into her night clothes and onto her skin. She jumps with a screams. Nishiko has wet on the bed!
Changing a cat's litter tray is not a pleasant thing as most peeps know too well. Don and I will tend to do a complete litter change every 2 days - I know this is not great and I feel so guilty about it, and the stench is unbearable. After reading Vicky's article I think I'm putting the girls through a lot worse than previously imagined and will now endeavout to change their tray every day from today.