It’s been interesting to me that people can develop allergies to things in mid-life and later, that they were never allergic to before. I think it’s happened to me with some pollens, and CATS!
I’ve had cats all my life, but only began having reactions to them in my ‘50s; and only in the past few years have had problems with the blooming trees in Spring.
(However, I’m surrounded with blooming trees now as I never was in my younger life..)
Oh, at first I thought you were talking about cats developing allergies. I have one that developed a grain allergy late in life. Probably because the store bought kibble is full of the stuff and it’s not normal for them to eat it.