In-laws have always had cats. I can manage 1 or 2 with anti-histamines and inhaler. We had our own cat for a while but I got used to him.
In-laws have just taken in a stray who has had a litter of 3. So now they have 6 cats, only 1 of who will be allowed outside so all hair will be she in their 3 bedroom bungalow. Plus the litter tray situation.
They know I am allergic to cats. I am usually quite rough when we stay there with the just the two cats they had. My only A&E trip due to asthma was while staying at their house. I have suggested to DH he will have to take the kids and visit without me. DH is not happy with this plan.