Mark Twain once quipped, “If you pick up a starving dog and make him prosperous, he will not bite you. This is the principal difference between a dog and a man.”

Many of the stories in Part One involve rescued companion animals rescuing a family member in distress. Is this, as Twain implied, gratitude for being adopted, loved, and fed? Does the fact of being rescued and cared for make any difference to the animal?

As Twain so tartly noted, it doesn’t always make a difference with people. We may never know what our companion animals understand about their circumstances nor if they remember when we first met. Yet, however it arises, the fact that a familial bond exists can seem to matter a great deal, and it often seems to inspire these jaw-dropping feats of courage.

A strong familial bond is evident with longtime pets, but sometimes the length of an acquaintance is strangely irrelevant. Owners sometimes describe connecting with animals instantly. Then, only days or even hours after meeting—with time for only a handful of meals—these new companions valiantly save their owners from death.