My 3 year old cat named Misty has started peeing in my air ducts about 3 weeks ago. 3 months ago is when we moved into our house that we are living right now. I have tried changing litter brands, I have tried Moving the litter box, I have used Natures Miracle to clean it up and hopefully dissuade her from doing it some more but to no avail she continues using the vents as her pee spot. Also she has recently gotten aggressive to my 15 month old son by biting him. This has all started withing 3 weeks and I do not know what to do! I do not want to get rid of her because I know she has been through a lot in her life before I received her. I just do not know what to do. She is spayed.