Two teenage girls have been photographed by the Duchess of Cambridge with their Holocaust-surviving grandfather.

Maggie Fleet, 15, and her sister Trixie, 13, have been pictured with grandfather Steven Frank, 84, as part of an exhibition marking 75 years since the end of the Holocaust.

Maggie and Trixie, who attend Watford Grammar School for Girls, have been featured in photos taken by Kate Middleton.

The duchess was among those behind the lens for the project and described the survivors in her portraits as "two of the most life-affirming people that I have had the privilege to meet".

Each of the portraits depicts the special connection between a survivor and younger generations of their family, who will carry the legacy of their grandparents.

One of Mrs Middleton's two portraits was of 84-year-old Steven Frank, originally from Amsterdam, who survived multiple concentration camps as a child.

The project was a collaboration between the Holocaust Memorial Day Trust, Jewish News and the Royal Photographic Society (RPS).

Trixie described the experience as "amazing" while sister Maggie added: "I think it helped put into perspective that he's just our Oupa - he's our grandpa as well as a Holocaust survivor."

Mr Frank and Maggie have previously told their story via the Newsround Special Finding my Family: Holocaust, for which they won a BAFTA.

Mr Frank will be the guest of honour at a Holocaust memorial service at Watford Grammar School for Girls on February 10. He will speak to Year 10 pupils about his experiences in concentration camps during World War II.

Sylvia Tai, headmistress at Watford Grammar School for Girls, said: "It will be a privilege to welcome Steven to our school for a special Holocaust memorial service. It is important that, 75 years on from the end of the Holocaust, our pupils continue to hear his story and learn from his experience."