The underneath - Kathi Appelt

There is nothing lonelier than a cat who has been loved, at least for a while, and then abandoned on the side of the road.
When an abandoned cat, about to have kittens, hears the lonely howl of a chained-up, abused hound dog, she seeks him out, and this unlikely pair become an unlikely family. Living underneath the porch of a old house deep in the American bayou, the kittens are safe, just as long as they stay in the Underneath. But it's a dangerous world out there, with alligators and snakes lurking in the waters - always watching and waiting... But one kitten's moment of curiosity sets of a chain of events sets off an astonishing chain of events, and so begins a gripping tale about the power of love and hate, the fragility of happiness, and the importance of keeping promises, whatever the cost.