Just claim they are emotional support cats, apparently anything goes in that case...was in J on AC 115 on 12-27 and the woman across the aisle from me had what looked more like a ferret than a dog which she held against her chest for the entire flight...I asked the FA (politely) if the animal wasn't supposed to be in a Carrier and was told in a very chastising manner that it was an emotional support dog, as if I was supposed to have known that...clearly the other PAX's need for emotional support from the ferret like canine was more important than my allergies.