51 Birch Street

Several months after documentarian Doug Block's mother dies, his father announces that he plans to sell the family's Long Island, N.Y., home and move to Florida with his former secretary, Carol "Kitty" Duffy. Though Doug always believed his parents had a happy marriage, his father's sudden decision makes him wonder if their relationship was more complicated than he realized. In the weeks before his father moves, Doug interviews family and friends to learn more about his parents.