Laskier was born in the Free City of Danzig (now Gda?sk, a port city in northern Poland), then a predominantly German-speaking autonomous city-state, where her father, Jakub (Yaakov) Laskier, worked as a bank officer. Her family was well off, her grandfather serving as co-owner of Laskier-Kleinberg and Company, a milling company that owned and operated a grist mill. In the early 1930s she moved with her family to the southern Polish city of B?dzin, from whence her father's parents had come. While there, in 1943, at the age of 14, Laskier wrote a 60-page diary in Polish, chronicling several months of her life under Nazi rule, which was not released to the public until 2005. photo

Laskier's family was forced to move to B?dzin's Jewish ghetto during World War II. Laskier was believed to have died in a gas chamber, along with her mother and brother, upon her arrival with her family in August 1943 at the Auschwitz concentration camp, at the age of 14. However, it was revealed in 2008 that she was not sent to the gas chambers. In a published account of her time in Auschwitz, Zofia Minc, who was a fellow prisoner, revealed that Laskier slept in the barrack next to her until falling victim to a cholera outbreak in December 1943. The girl pushed Laskier, still alive, in a wheelbarrow to the crematorium. Rutka begged Zofia to take her to the electric fence where she could kill herself, but an SS guard following them would not allow it.

Rutka's father was the only member of the family who survived the Holocaust. Following World War II, he emigrated to Israel, where he remarried and had another daughter, Zahava Scherz. He died in 1986. According to Zahava Scherz, interviewed in the BBC documentary "The Secret Diary of the Holocaust" (broadcast in January 2009), he never told Scherz about Rutka until she discovered a photo album when she herself was 14, which contained a picture of Rutka with her younger brother. Zahava explains that she asked her father who they were and he answered her truthfully, but never spoke further about it. Zahava went on to explain that she learnt of the existence of Rutka's diary in 2006, and she expressed how much it has meant to her finally to be able to get to know her half-sister, to whom she felt a closeness after reading her diary.

From January 19 to April 24, 1943, without her family's knowledge, Laskier kept a diary in an ordinary school notebook, writing in both ink and pencil, making entries sporadically. In it, she discussed atrocities she witnessed committed by the Nazis, and described daily life in the ghetto, as well as innocent teenage love interests. She also wrote about the gas chambers at the concentration camps, indicating that the horrors of the camps had filtered back to those still living in the ghettos.

The diary begins on January 19 with the entry "I cannot grasp that it is already 1943, four years since this hell began." One of the final entries says "If only I could say, it's over, you die only once... But I can't, because despite all these atrocities, I want to live, and wait for the following day."

In 1943, while writing the diary, Laskier shared it with Stanis?awa Sapi?ska (21 years old, at that time), whom she had befriended after Laskier's family moved into a home owned by Sapi?ska's Roman Catholic family, which had been confiscated by the Nazis so that it could be included in the ghetto.. ISBN 83-89956-42-X.

• Laskier, Rutka (2007). Rutka's Notebook: January-April 1943. Foreword by Dr. Zahava Sherz; historical introduction by Dr. Bella Gutterman. Jerusalem, Israel: Yad Vashem Publications.[1]