On my 10th birthday, I got a puppy. I was so shocked—I had wanted a dog for as long as I could remember—and so overwhelmed with happiness that I burst into tears. For the next 14 years, Happy, a beagle, charmed everyone he met. And when he passed, all of us who had known him mourned, as we would for any loved one. More than half of American households have a pet—that is, an animal kept primarily for companionship. And despite the fact that these housemates may bear scales, fur, fins or feathers, people often view their animals as family members. In 2014 we spent an estimated $58 billion on our animal companions and untold hours caring for them.