Stephanie Shain, director of the Stop Puppy Mills Campaign for the Humane Society of the United States, completed an 8-month investigation and the results are grim. We've all heard about the conditions in puppy mills but were you aware that most pet stores buy their puppies from these sorts of enterprises? On this week's "Good Dog", we hear from Stephanie Shain, director of the Stop Puppy Mills Campaign for the Humane Society of the United States.