Anne Frank’s diary entries record the 25 months she spent hiding from Nazis from 1942 to 1944 with her family and others in a secret attic annex in occupied Amsterdam. Frank’s father, the only member of the family to survive after they were seized by the Gestapo and removed to a concentration camp, published the diary after the war, turning the teenager into a universal symbol of hope and resilience.

The book, with its red-checked cover, was not written with an eye toward publication. Her private thoughts and observations were for her eyes only, very much “The Diary of a Young Girl,” as its title suggests.

Now researchers in the Netherlands have discovered in the diary a secret hidden for decades, obscured from prying eyes by brown paper that had been meticulously pasted over the pages.

On two pages, Anne, who was 13 years old at the time, penned four “dirty” jokes and more than 33 lines explaining sex, contraception and prostitution, the Anne Frank House announced Tuesday. The entry, dated Sept. 28, 1942, also included five crossed out phrases, the museum said.

The recently publicized pages of hidden text serve to highlight “Anne the girl,” and her “inquisitive” and “precocious” personality, the Anne Frank House said.

“Anyone who reads the passages that have now been discovered will be unable to suppress a smile,” Frank van Vree, director of the Netherlands Institute for War, Holocaust and Genocide Studies, said in a statement. The ‘dirty’ jokes are classics among growing children. They make it clear that Anne, with all her gifts, was above all also an ordinary girl.”

The passages were revealed by image-processing technology. Using photos of the pages taken in 2016 as part of a regular check of the diary, software helped decipher the words, the statement said.

In an effort to save pages of her precious diary that had been “spoiled,” Anne decided to use some of the space to jot down risque jokes she may have heard from her father or on the radio, the Anne Frank House said.

“A man had a very ugly wife and he didn’t want to have relations with her,” she wrote, as translated from Dutch by the Associated Press. “One evening he came home and then he saw his friend in bed with his wife, then the man said: ‘He gets to and I have to!!!’”

She also included this suggestive quip: “Do you know why the German Wehrmacht girls are in Holland? As mattresses for the soldiers.” (The Wehrmacht was the German term for the country’s armed forces.)


The most frequently published photograph of Anne Frank is prepared for display in 2004 at the Holocaust Museum in Houston. (Pat Sullivan/AP)

Following the jokes, Frank delved into sex education, pretending in the entry that she was teaching someone else, the museum said.

“I sometimes imagine that someone might come to me and ask me to inform him about sexual matters,” Frank wrote in Dutch, according to the New York Times. “How would I go about it?”

While attempting to explain these “sexual matters,” Frank used highbrow phrases such as “rhythmical movements” to describe sex, and “internal medicament,” to talk about contraception, the New York Times reported.

Being a teenage girl, she made sure to include a section about periods, too, saying menstruation 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,” according to the AP.

On prostitution, Frank wrote: “All men, if they are normal, go with women, women like that accost them on the street and then they go together.” She added: “In Paris they have big houses for that. Papa has been there.”

It is unclear why Frank’s musings were covered with the sticky brown paper, but researchers say it may have been done by the teenager, who was trying to hide the content from her father or anyone else living in the cramped attic quarters.

On Oct. 3, 1942, she wrote, “Daddy is grumbling again and threatening to take away my diary. Oh, horror of horrors! From now on, I’m going to hide it,” according to a frequently asked questions page posted by the Anne Frank House.

This entry was after she had filled the concealed pages, but the museum said Anne would “regularly reread her diary entries and made changes to them.”

Despite being shrouded in mystery for more than 70 years, the uncovered pages “do not alter our image of Anne,” the Anne Frank House said. The writings were not unusual for the teen, who had other diary entries about sex and “regularly” recorded dirty jokes, the museum said.

The pages are significant because they show Frank’s first attempts to develop her literary voice, the AP reported.

Ronald Leopold, executive director of the Anne Frank House, told the AP the entry is an early example of how Frank “creates a fictional situation that makes it easier for her to address the sensitive topics that she writes about.”

In response to a question about whether it is right to publish pages that had intentionally been covered up, the museum said Frank’s diary is “a world heritage object with great historical value, and this justifies research into it.”

“Given the great public and academic interest we have decided … to publish these texts and share them with the world,” Leopold said in a statement from the museum. “They bring us even closer to the girl and the writer Anne Frank.”