They operate under names like Granny’s Junction. Inside, among cubbies for winter coats, boxes of Legos and kitchen tables surrounded by booster seats, they offer a lifeline to millions of working mothers and fathers. The nation’s home-based child care providers represent millions of single business owners –women, mostly – whose entrepreneurial spirit and operating ingenuity are surpassed only by their willingness to clean the noses and backsides of other people’s children. In Michigan, roughly 40,000 of the state's 70,000 day care owners were perhaps too busy changing diapers, reading stories and making lunches to notice a random piece of mail...