Royals This 1947 Letter from Queen Elizabeth Reveals How She Fell in Love with Prince Philip The Queen wrote to author Betty Shew about her relationship with her then-fiancé By Diana Pearl Published on April 14, 2016 04:45 PM Share Tweet Pin Email Trending Videos Photo: Hulton Archive/Getty They’ve been together for 73 years – and the beginnings of Queen Elizabeth and Prince Philip‘s love story was epic from the start. A letter from the Queen to author Betty Shew, who was writing a souvenir book in honor of the Queen’s 1947 wedding, casts intimate light on the then-Princess Elizabeth’s private thoughts about beginnings of her relationship with Prince Philip – then Philip Mountbatten. The letter was part of a collection of royal memorabilia that was up for auction in 2016. The two first met, the Queen writes, at the Royal Naval College in July 1939, just before World War II broke out. She was just 13 years old but was charmed by the 18-year-old naval cadet. After the war began, the two only saw each other “occasionally” when Philip was on leave. As their relationship grew, the two started spending more time together, especially when Philip accepted a job at an officers’ school in England and was able to visit more. “He’d spend weekends with us, and when the school was closed he spent six weeks at Balmoral,” she wrote. “It was great luck his getting a short job first them!” Queen Elizabeth and Prince Philip on their wedding day. Popperfoto/Getty Queen Elizabeth and Prince Philip on their wedding day Queen Elizabeth Shares Sweet Throwback Photo of Prince Charles in Honor of His 72nd Birthday Further into their relationship – but before their engagement – they’d drive out in his sports car together. “Philip enjoys driving and does it fast!” she wrote. “He has his own tiny M.G. which he is very proud of he has taken me about in it, once up to London, which was great fun, only it was like sitting on the road, and the wheels are almost as high as one's head.” Can't get enough of PEOPLE's Royals coverage? Sign up for our free Royals newsletter to get the latest updates on Kate Middleton, Meghan Markle and more! She also discussed her new engagement ring, telling Shew that Philip designed it himself.