Red is a novel written by Jack Ketchum. It was first published in 2002.
Description[]
The old man hears them before he sees them, the three boys coming over the hill, disturbing the peace by the river where he's fishing. He smells gun oil too, too much oil on a brand-new shotgun. These aren't hunters, they're rich kids who don't care about the river and the fish and the old man.
Or his dog. Red is the name of the old man's dog, his best friend in the world. And when the boys shoot the dog -- for nothing, for simple spite -- he sees red, like a mist before his eyes. And before the whole thing is done there'll be more red. Red for blood...