Alathea Fitzalan Howard was a teenager when World War II began and she evacuated to her grandfather's Windsor estate. There, her nearest playmates were a pair of sisters living across the park: the Princesses Elizabeth ("Lilibet") and Margaret. Alathea chronicled this uncommon friendship in her personal diaries, recording notes about the girls' drawing classes, dance lessons, and Girl Guides meetings. But while Alathea's brief entries initially seem a bit frivolous, a more complex, poignant story gradually unfolds. Her devotion to the princesses is less about their lofty station and more about her envy of their loving family and her gratitude for the queen's kindness—a stark contrast to Alathea's own unhappy family. And her observations about her friend Lilibet— thoughtful, unpretentious, reserved—offer personal insight into the child who would grow up to become Great Britain's longest-reigning monarch.