Researchers have uncovered two previously unpublished pages of Anne Frank’s diary. It was Anne Frank herself who covered them with brown gummed paper, blacking out what she had written on those pages on September 28th, 1942, two and a half months after she went into hiding with her family in the secret annex.

The content was revealed using digital technology. In 2016, every page of the diary was photographed as part of a condition check for conservation purposes. The page, front and back, covered with brown paper was held up vertically and backlit with a flash. The high resolution photograph was then analyzed with image-processing software which was able to distinguish the writing underneath the paper from the writing on the reverse sides.

On those two pages, Anne had crossed out five phrases, written four “dirty” jokes and her musings on sex education and prostitution, 33 lines worth. The top of the first page Anne stated her intent: “I’ll use this spoiled page to write down ‘dirty’ jokes.” It’s not clear why she thought it was spoiled.

In the afternoon of Monday 28 September 1942 workmen were busy removing the office toilet, immediately below the secret annexe, so any sound from the hiding place was dangerous and had to be avoided at all costs. Anne was writing. In her diary Anne pretended that she was corresponding with a number of imaginary friends, and that day she wrote a total of four “diary letters”: to her whole circle of imaginary friends, to Kitty, to Pien and to Loutje.

On that day she also leafed through her entire diary and added comments to no less than 18 earlier “diary letters”. She wrote additions to photo captions, to a letter from her father and to a letter from her friend Jacqueline van Maarsen that she had earlier stuck into her diary. What is more, Anne also wrote of how afraid she was that the people in hiding would be discovered, and how much support her diary gave her. She made a list of twelve signs of beauty and assessed the extent to which she lived up to them. It all goes to show that on that day Anne was closely scrutinising herself, her own sexuality and the world around her.

In the 33 lines about sex, Anne, who was 13 at the time, noted that a girl gets her period when she is around 14 years old and that is “a sign that she is ripe to have relations with a man but one doesn’t do that of course before one is married.” Her remarks on prostitution are also direct with a personal angle: “All men, if they are normal, go with women, women like that accost them on the street and then they go together. In Paris they have big houses for that. Papa has been there.”

Anne reread her diaries often during her years in hiding and continued to make changes to her old entries as she saw fit. She crossed out parts of it, added new text, rearranged the wording. These are the only two pages she covered completely. What drove this choice is unknown. There are other dirty jokes and frank reflections on sex, puberty and body image in Anne’s diaries, and she never covered them up. She did evince concern that her father might take her diary away as he’d threatened to do, and apparently Mrs. Van Pels creeped her out when she said she wanted to read them.

The covered pages do not alter our image of Anne. She regularly recorded “dirty” jokes or dealt with sexuality in her diary. Over the decades Anne has grown to become the worldwide symbol of the Holocaust, and Anne the girl has increasingly faded into the background. These – literally – uncovered texts bring the inquisitive and in many respects precocious teenager back into the foreground.