Duchess Kate added a touching personal detail to her outfit this week

It's said without the codebreaking work done at Bletchley Park during World War II, the Allies might not have won the conflict. Experts believe the operations at the 19^th century Buckinghamshire mansion also shortened the war by two or three years. Duchess Kate visited the park earlier this week, and showed off her personal connection to the estate with a detail on her dress some might have missed.

Kate’s grandmother Valerie Glassborow and her great-aunt Mary – twins – worked at Bletchley Park during the War. The two served as duty officers, according to the Telegraph, and worked in Hut 16 (Hut 6 until February 1943), which was centred on processing and decrypting Enigma messages sent by the German army and air force.

Kate shared a laugh with former Bletchley codebreakers Elizabeth Diacon (L), Georgina Rose (2nd L), Audrey Mather (2nd R) and Rena Stewart (R) during her visit. Photo: © Heathcliff O’Malley/AFP/Getty Images

The Duchess of Cambridge met with former codebreakers Elizabeth Diacon , Georgina Rose, Audrey Mather, Rena Stewart during her visit – and did you notice they were all wearing the exact same pins? Kate’s brooch was owned by her grandmother, and all five of the badges look like rotors from Enigma machines.

Here are some rotors from an Enigma machine a closer look at Kate’s brooch. Photos: © Wikipedia / Max Mumby/Indigo/Getty Images

Nazi Germany used Enigma machines to transmit encrypted messages in World War II. While Polish mathematicians including Marian Rejewski had already deciphered the Enigma in 1932 and had shared this information with the British government, the Germans changed their Enigma cipher system on a daily basis, making the codes harder to understand and break.

The Queen and Prince Philip were shown an Enigma machine on a visit to Bletchley Park in 2011. Her Majesty was very keen to press its buttons. Photo: © Arthur Edwards/Getty Images

At Bletchley Park, a team that included mathematician and computer scientist Alan Turing created a machine called The Bombe, which helped reduce the amount of work by codebreakers in cracking Enigma messages. This work and other codebreaking is credited with significantly reducing the time of the war.

Prince Charles was shown a rebuilt Bombe machine during a visit to Bletchley in 2008. Photo: © Tim Graham Picture Library/Getty Images

Kate also met a group of children who are learning coding using Enigma machines while visiting Bletchley, and spoke about her connection with them.

“It’s quite interesting how you’re all learning about coding in school, and now you can look back at how it first started,” she said, according to the Telegraph. “My granny and her sister worked here. It’s very cool. When she was alive, sadly she could never talk about it. She was so sworn to secrecy that she never felt able to tell us.”

There are two bricks honouring Kate’s relatives at Bletchley Park. Photo: © Heathcliff O’Malley/AFP/Getty Images

Speaking to the four codebreakers, Kate told them that it was “lovely” that their work is “being celebrated.” She told them the children she had met with understood codebreaking is extremely complicated. “They have got a real appreciation of what you were doing,” the Telegraph reports her saying. She also told the four women it was “a real honour” to have met them.

MORE: Duchess Kate looks pretty in recycled polka dot dress for Bletchley Park

Kate’s grandmother and great-aunt and the four codebreakers mentioned above were by far not the only women to work at Bletchley. Jane Hughes Fawcett, who decoded a message that led to the sinking of the German battleship Bismarck, also worked in Hut 16. About 8,000 women worked at Bletchley during the war, making up about 75 per cent of those who were there.