When Harry Kenner stopped for the two hitchhikers, he could not guess that they would change his life. Not only would he fall in love with one of them, he would fall hard for both of them. One of the hitchhikers, Vally, is seven years old and, as a Down Syndrome child, possesses an extra chromosome in her genetic make-up. Her mother calls it "a happiness gene" - an "extra" given her by a kindly Creator. It is her sweetness and vitality, as well as her vulnerability that first captures Kenner's heart. Not long after, Vally's unwed mother, Katherine, finds her way into the same heart. Her reckless courage both frightens and attracts Kenner who feels compelled to help in her fight to keep her child. This is the story of a dying man who suddenly discovers something worth living for. He finds himself pushed to the limit to succeed in a field in which he had heretofore failed. When failure seems about ready to overcome him, the needs of his charges push him past exhaustion and despair to achievements he could not have imagined a few months earlier.