The great-granddaughter of a woman who is mentioned in the historic diary of Anne Frank met staff at the Amsterdam museum that bears the Holocaust victim’s name for a special behind-the-scenes tour.

Tali Blitz’s great-grandmother, Sientje Blitz, introduced the Frank family to a woman who would help them survive for two years in hiding, and was mentioned in Anne’s diary.

The 12-year-old, who lives in Hampstead, visited the Anne Frank Museum earlier this month as part of a trip organised by her school, Immanuel College, in Hertfordshire.

Museum staff were unaware of Tali’s connection to Anne until a teacher mentioned it during the visit.

Whilst living in Amsterdam in the early 1930s and working as a travelling saleswoman, Tali’s great-grandmother introduced Anne’s father, Otto Frank, to Miep Gies.

Miep helped looked after the family for almost two years when they went into hiding in the attic of Otto’s office building. Whilst continuing her job in the office, Miep secretly delivered food each day to the Frank family upstairs.

Sientje is referred to in Miep’s book, written after the war, as ‘‘Mrs Blik’’, the nickname given to Tali’s great-grandmother in Anne’s diary to disguise her true identity.

Tali said: “This was a really unique experience which helped me not only to feel a close connection with my great-grandmother, but also with the story of Anne Frank.”

Fortunately Sientje, her husband and three children – the youngest of whom was Tali’s grandfather, Albert – emigrated to South Africa before the outbreak of the Second World War.

Anne and her family were not so lucky. Otto was the sole survivor of the secret annexe.

Susan Ribeiro, head of Year 7, said: “I spoke to the guide and explained who Tali was.

“We were then given access to the office area, where Tali’s great-grandmother would have met Otto Frank.

“We were also allowed into the kitchen, where the jams would have been made, and into the gardens.

“At the end of the tour, the school presented the Anne Frank Museum with a copy of the school’s siddur [a Jewish prayer book], and inside Tali wrote a personal message to Anne and included a photo of her great-grandmother.”