Edison currently has a cast iron lock on Least Favored Feline status chez nous. We've had a Mystery Pisser hereabouts for a couple of weeks now and were having quite the time identifying the culprit.
First we thought it was Nosey. Urine was found on a chair Nosey likes to sit on. He had been there for quite a while near the time the urine was found. Also, it was during the cats' daytime nap (roughly, 9 AM - 4 PM) and there hadn't been much feline movement other than perhaps a stretch and maybe rolling over to the other side. But then urine was found in a very wrong location during a time when Nosey was confined elsewhere iot get a urine sample from him for his regular testing.
Then we thought it might be Miles bc he was growing up, he hadn't been neutered yet and maybe he was taking up marking as a hobby. Then he was ruled out when the Mad Pisser struck while Lizzie and Miles were confined elsewhere iot fast before their spay and neuter surgeries.
Finally, we got a clue: Edison peed at the file cabinet right in front of Kevin yesterday morning. Nothing circumstantial about that! Edison is confined in the bathroom tonight iot get a urine sample for testing to rule out medical causes for his inappropriate urination. (It must seem like we're forever confining one cat or another for some reason or another.) It's probably behavioral in which case he'll receive medication. I hope Edison urinates in the almost empty litter box tonight and not just up against the wall or the side of the tub as per his current MO.