"The mother cat had been quite upset when she first saw the blue kitten. She had looked fearfully then toward the river. For, like all cats, she had heard that a blue kitten could learn the river's song. Any kitten has a hard enough time to find a home for himself. For every kitten must find a hearth to fit his song. But a kitten who listens to the river and learns the river's song has the hardest time of all. Not only must the kitten who sings the river's song find a hearth to fit that song, but he must teach the keeper of that hearth to sing the same song. The river's song is very old. And mortals who have ears to hear and hearts to sing are fewer than few."