My SIL swears that she is very, very, very allergic to cats. Back when we had an indoor cat she could visit for hours with no problems as long as she didn’t *see* the cat. But if the cat walked into the room where she was it triggered immediate death throes. It was the most awful gagging/choking/crying/coughing/sneezing fit you ever saw outside of a ICU. Her nose would run like a faucet and the tears would flow down her reddened face.
Of course I was the only one that noticed that she is only allergic to visible cats. All of my outlaws still talk about her deadly allergy. I can’t argue with any of them but if my wife mentions it I always suggest that she could get a Cheshire cat and then swagger off smiling smugly to sleep on the couch.