The Duchess of Cambridge was left visibly moved as she spoke to two Holocaust survivors, who told her: "All it takes for evil to triumph is for good people to remain silent."
Kate was reunited with survivors Zigi Shipper, 91, and Manfred Goldberg, 90, during an emotional video call to mark Holocaust Memorial Day on 27 January.
The trio highlighted the importance of educating young people about the persecution of six million Jewish men, women and children by Nazi Germany during World War Two.
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As young boys, Zigi and Manfred both spent time in ghettos and a number of labour and concentration camps, including Stutthof near Danzig (now Gdansk) where they met for the first time in 1944. Built in 1939, Stutthof was the first camp to be built outside German borders and was one of the last camps liberated by the Allies in May 1945.
The Duchess first met Zigi and Manfred during a visit to Stutthof concentration camp near Gdansk during her tour of Poland with Prince William in 2017.
Kate's call with the friends was organised by the Holocaust Educational Trust (HET), which works in schools, universities and local communities to educate young people from all backgrounds about the Holocaust and the vital lessons to be learnt from it.
The Duchess, Zigi and Manfred spoke to two students who have become HET Ambassadors, Farah Ali and Maxwell Horner.
Maxwell told them he had been inspired both by a family visit to Anne Frank's house in Amsterdam and his visit to Auschwitz.
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The Duchess hailed Zigi and Manfred for their "strength and bravery"
"I've always had from quite a young age a strong passion about human rights and injustice. I jumped at the opportunity," he said. "I feel the Holocaust is a focal point of injustice. It was the biggest injustice of modern history. If we learn about the Holocaust, we can make sure it doesn't happen again, make sure we recognised the signs leading up to genocide."
Asked by the Duchess how she felt hearing the men's stories, Farah said: "There are no words to describe it."
Speaking about his work lecturing the younger generation, Manfred said: "What I end up telling them is...that please remember all it takes for evil to triumph is for good people to remain silent. And I do get feedback that indicates that this is taken aboard.
"I have been told time and again, that leaning about the Holocaust from a textbook is rather dull and doesn't make an impact. But to listen to a survivor makes an incredible impact."
The trio also spoke with HET youth ambassadors Farah and Maxwell
Kate agreed, saying: "We all have a role to play, all generations have a role to play in making sure the stories that we have heard from Zigi and Manfred today live on and ensure that the lessons that we have learnt are not repeated in history for future generations.
"I am really glad there is the younger generation flying the flag for this work.
"Manfred and Zigi, I never forgot the first time we met in 2017 and your stories have stuck with me since then and it's been a pleasure to see you again today and you are right Manfred, it's important that these stories are passed onto the next generation."
Kensington Palace shared photos of the Cambridges' visit to Stutthof in 2017
Earlier on Wednesday morning, Prince William, 38, and Kate, 39, shared poignant photos from their visit to Stutthof in Poland in 2017, where they first met Holocaust survivors, Zigi and Manfred.
The caption on the social media post read: "As young boys, Zigi and Manfred both spent time in ghettos and a number of labour and concentration camps, including Stutthof in Poland where they met for the first time in 1944, and remain friends to this day.
"Of the 110,000 men, women and children who were imprisoned in the camp during the Holocaust, as many as 65,000 lost their lives - including 28,000 Jews.
"Together on 27 January, the anniversary of the liberation of Auschwitz-Birkenau, the largest Nazi death camp, we bear witness for those who endured genocide, and honour the survivors and all those whose lives were changed beyond recognition.
"We must never forget. #HMD2021."
William and Kate first met Zigi Shipper and Manfred Goldberg in 2017
The Duke and Duchess were pictured looking visibly moved by their visit to the former concentration camp in Gdansk in 2017.
Last year on the 75th anniversary of the liberation of Auschwitz, Kate shared two powerful portraits she'd taken of survivors with their grandchildren at Kensington Palace.
William and Kate's touching social media post comes after the Prince of Wales and the Duchess of Cornwall recorded a special message to open the 2021 virtual Holocaust Memorial Day event, taking place on Wednesday 27 January.
Charles has been Patron of the Holocaust Memorial Day Trust since 2015, and last year he attended the World Holocaust Forum at Yad Vashem, Jerusalem.
Camilla also attended commemorations in Poland last January to mark the 75th anniversary of the liberation of Auschwitz-Birkenau.
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