Kate Middleton reveals her pride about WWII code-cracking grandmother

For a charity project, the 34-year-old royal offered rare personal insights into her family history.

The Duchess of Cambridge, née Kate Middleton, took advantage of the release of The GCHQ Puzzle Book, the first puzzle book launched by the Queen’s Government Communications Headquarters, inspired by the men and women who deciphered codes during World War II (1939-1945).

In a foreword to the book, Catherine paid tribute to her grandmother, Valerie Glassborow.

“I have always been immensely proud of my grandmother, Valerie Glassborow, who worked at Bletchley Park during the Second World War,” Kate wrote.

“She and her twin sister, Mary, served with thousands of other young women as part of the great Allied effort to break enemy codes. They hardly ever talked about their wartime service, but we now know just how important the men and women of Bletchley Park were, as they tackled some of the hardest problems facing the country.”

All proceeds from the book will go to Heads Together, an organization founded by Kate, William and Harry that campaigns against the stigmatization of mentally ill people.

Last week the royal trio attended a Heads Together event at the London Eye, in honor of World Mental Health Day.