A new book about women in the British royal family claims Princess Diana once had a teenage crush on Prince Andrew — and acted on it with anonymous Valentine’s Day cards. According to People Magazine, author Catherine Mayer writes in Divide and Rule: Royal Women and Their Battles that Diana sent the notes every year until she was about 15 or 16. The detail adds a fresh chapter to Diana’s early royal orbit, years before she married the future King Charles and became one of the most watched women in the world.

Catherine Mayer Details Diana’s Teenage Crush

In the book, Mayer describes Diana’s feelings as a distant teenage passion rather than a serious romance. "The schoolfriend says that every year until Diana turned fifteen or sixteen, she sent Andrew a valentine card, anonymously of course," Catherine Mayer writes. Mayer also places the claim in a wider portrait of Diana’s early ideas about love, arguing that the future princess longed for a fairy-tale version of romance. That framing fits with the image of a young aristocrat growing up close to royal circles, but still imagining love from afar.

Diana’s Royal Ties Started Long Before Marriage

Diana was not an outsider when she entered the royal family. She was born at Park House on the Sandringham Estate, and her family had deep links to the monarchy. Her grandmother, Ruth Roche, Baroness Fermoy, served as a lady-in-waiting to the Queen Mother. Diana’s sister Sarah also briefly dated Charles in the late 1970s, and it was through those family connections that Diana first met him. By 1980, Charles was courting Diana, setting in motion the engagement and wedding that would define a generation of royal history.

Sarah Ferguson and Prince Andrew Later Became a Match

The Prince Andrew detail carries extra intrigue because Diana later helped connect him with Sarah Ferguson, her childhood friend and fourth cousin. Ferguson recalled the moment years later: "I said to her, 'Oh, Andrew's really good-looking.' And she said, 'Duh, Fergs!' " Sarah Ferguson told PEOPLE. Andrew and Ferguson married in 1986, making them one of the era’s most talked-about royal couples. In that sense, the story comes full circle: the teenager who once admired Andrew from a distance later played a part in his marriage.

The Book Revisits Diana’s Place in Royal History

Mayer’s book looks at eight women across the British monarchy, including Diana, Kate Middleton, Meghan Markle, Queen Elizabeth and Queen Camilla. The new claim stands out because it adds a personal note to Diana’s pre-marriage years without changing the broad outline of royal history. It also arrives as interest in Diana’s life remains strong nearly three decades after her death in 1997. Small details like this continue to shape public understanding of how closely her story was tied to the House of Windsor even before her wedding day.