I am severely confused by this and need some help figuring out what the heck is going on. I'll give as much detail as I can, so bear with me. 1) Two weeks ago my wife and I noticed a mildew smell coming from our spare bedroom. It seemed to be coming from the closet, but after a brief visual inspection we found nothing. 2) My wife went on a business trip for a week, and during that time the spare bedroom was closed and never used (normally one of us goes to sleep there every night, since we are on different schedules...or due to snoring heh). A couple days ago when she returned I walked past the room and told her I smelled cat, but she didn't smell it. 3) Today we find half a dozen cat sized urine stains on the carpet leading out of the closet! We took everything out of it, and found two throw pillows soaking wet and covered in mold (so the mold mystery is solved at least). The smell of cat was instantly obvious to everyone now. So those are the facts and context. I checked the vents, and crawl space, but found no signs of animal or disturbances. There was no feces whatsoever in the room. There are no holes in the wall, or crawlspace. I now fear there is some sort of feline (a weasel??) living in my house, but the weirdest thing is that I have THREE dogs who roam the house at all times. That particular room is kept closed to keep the dogs out though. That only makes the mystery more odd, because there is no way in or out--besides the register vents, which were not disturbed and only have a half inch opening. Ideas anyone?