The Youngs are women in a committed relationship who love and care for and look after each other. They share domestic duties and financial responsibilities. They share a bed and make love. They have a child (courtesy of sperm donation and in vitro fertilization) and intend to have two more. They were united in a ceremony in which they wore beautiful white wedding gowns and were walked down the aisle by their fathers. They are just like any ordinary Massachusetts opposite- or same-sex married couple. Only they’re not a couple. Doll, Kitten, and Brinn Young are a throuple. And,...