Honestly, the first time I heard it, I thought Mabel was choking. She was a 10-month-old Lab mix, full of energy and bad decisions. One minute she was fine. The next, she was making this sound—a dry, hacking, almost goose-like honk, that sent me running across the room. I flipped her mouth open, checked her throat, half-convinced she’d swallowed a squeaker toy. Nothing there. That was my introduction to kennel cough. And I learned fast that this sound, as terrifying as it is, is usually not an emergency. ...

You walk into the living room and there it is, a puddle of white foam on the rug. Your cat is standing nearby, looking slightly embarrassed. Maybe a little confused. You’re worried. I get it. I’ve been there with my own cat, Milo. He was a rescue, about 2 years old, all attitude and appetite. The first time I saw him hack up white foam, I panicked. I called my vet at 9 PM like a crazy person. Turns out, it was nothing serious. But sometimes it is. ...