DS (1 yr) seems to be allergic to my cats. I've had them for 7 yrs now and since he got mobile @ 6months he seems to be always have a runny nose when we r at home. He didn't when we went on holiday and it gets better at childminders. I'm convinced it is the cats and actually separated them (but still have common area which both use). Some lost some growth spurts as a result of his allergy. I got some commercial grade air purifiers (useful for pet dander, virus and bacteria, etc) but the room gets very chilly with them -as i have to use 2 at a time to make it work. I turned them off for the first time in 3 months for 12 hours and DS's nose is running again. Has anyone experienced this? If so what did you do about it. I want to be fair to DS and cats, what is the best option?