My mil is allergic to cats and dbil has one.
Mil allergy has got worse in severity in time, what was a take an anti histamine before going to the house is now take an anti histamine before having anyone with a cat come to visit her house , and people who have cats have to put on clean clothes and she still feels exhausted and unwell later
It started as would just take an antihistamine, as she aged it then became can't spend the night there, to can't go in at all.
DMil now can't step foot in dbil new house . This means she's never been able to baby sit in the house, go round for dinner, attend any of the functions at the house eg kids birthday parties. She's never set foot in her grandchildrens bedroom etc
There's distance involved for us so popping into see them in the garden isn't too attractive but even with that as she gets older she needs to enter to use the toilet more etc which she can't do. S
It's frustrating for us because it means any care needs for dpil get passed to us as they've not been able to stay there to recoup from operations etc and dbil has to arrange child care, cat care etc to come to pil.
Prior to the cats dpil would often spend a few nights in the summer, and often spend a week or so just playing with the grand kids etc but that's obviously stopped now
When they got the first cat it was excusable as they didn't predict the severity of allergies increasing with age, and the toll antihistamines can take on older people, when they got other cats following that it was hurtful.
I doubt my dpil have ever said anything but it has really impacted their relationship with dbil family and it comes across as purposefully excluding them