The Nazis came for Marta Wise on her birthday. She was only 10 but, as a Jew in Hitler’s Europe, had long before lost any semblance of normal childhood. Marta had spent two years on the run or under an assumed identity when the truck stopped outside her apartment in Slovakia to take her away.

She arrived on Nov. 3, 1944, at Auschwitz-Birkenau, the Nazi death camp in occupied Poland, where she was subjected to the medical experiments of Josef Mengele, the SS physician known to his victims as the “angel of death.” Her survival, she later said, she owed to luck, to the companionship of her sister Eva – who was arrested and imprisoned with her – and to hope.

When the Soviet army entered Auschwitz on Jan. 27, 1945, Marta weighed 37 pounds. She and Eva are among the 13 children who appear in a picture taken by a Soviet photographer shortly after the camp was liberated, a portrait of barest survival and, today, one of the most haunting images of the Holocaust.

Wise, 88, died May 19 at a hospital in Jerusalem. Yad Vashem, the Holocaust memorial in Israel, announced her death but did not cite a cause.

Wise’s testimony, which she shared with groups from around the world as a guide and speaker at Yad Vashem, had grown increasingly valuable in the later years of her life, as the number of living survivors dwindled, and as child survivors increasingly became the bearers of firsthand memory of the Holocaust.

As a 10-year-old who escaped death at the largest Nazi killing center, Wise was by any measure extraordinary. Of the 6 million Jews murdered in the Holocaust, nearly 1 million died at Auschwitz. According to the camp’s memorial and museum, only about 500 prisoners under the age of 15 were alive at the time of liberation.

Reflecting on her months in the camp, Wise said she remembered mainly her fear, her hunger and the cold. “I’m not sure how much I understood,” she remarked years later in an interview recorded by Yad Vashem. “I was a kid, after all. But it was a different world … It wasn’t from this world, Auschwitz.”

Marta Weiss was born in Bratislava, in what was then Czechoslovakia and is now Slovakia, on Oct. 8, 1934. She was the fourth child in an Orthodox Jewish family that would eventually grow to include eight daughters and one son.

Her father, an affluent businessman, owned spinning and weaving mills as well as a retail store. Wise remembered her mother as an elegant woman, ever stylish even as she looked after her many children.

Wise had a happy childhood, surrounded by her siblings, cousins, grandparents and other relatives in the stately residence where the family lived near Bratislava’s presidential palace.

But the dismemberment of Czechoslovakia in the Munich Agreement of 1938, in which Nazi Germany was permitted to annex the German-speaking Sudetenland in exchange for Hitler’s empty promise of peace, soon upended life for Jews in Slovakia.

Although formally independent, Slovakia became essentially a satellite state of Nazi Germany and, according to the U.S. Holocaust Memorial Museum, was the first Axis partner to agree to the deportation of Jews in accordance with what the Nazis termed the Final Solution.

Despite her youth, Marta began to intuit the threat as she saw signs forbidding “Jews and dogs” in the park where she had once played. Her father lost his businesses amid the worsening antisemitic persecution. In 1942, after he was arrested and released for ransom, he and his wife set about scattering their children in places they hoped would afford greater safety.

Marta was spirited into Hungary, which was not yet occupied by the Germans, to live with relatives in the town of Sarvar. After the Germans took over the country in March 1944, she was smuggled back to Bratislava, making part of the journey on foot through wheat and cornfields.

Her parents then sent her with her sister Eva, three years her elder, east of Bratislava to the city of Nitra, where the girls lived with a nanny, posing as Catholic children orphaned in wartime bombings.

They attended school and Sunday church services, rigorously keeping their cover. For an added measure of protection, Eva befriended the daughter of a high-ranking SS officer, who treated her with affection, often challenging her to games of chess.

One day, Wise recounted, the SS officer remarked on the upcoming Jewish holidays of Rosh Hashana and Yom Kippur.

Many Jews had already been deported from Bratislava. On the High Holy Days, the officer said to Eva, any who remained would “come out of hiding like rats out of their holes” to attend religious services. The Nazis would take the opportunity, he declared, to make Bratislava “Judenfrei” – free of Jews.

Eva managed to send word of the coming roundup to her parents, who passed the warning to other Jews also in hiding in Bratislava. At least for the moment, they owed their safety to a young girl.

Marta and Eva’s arrest came as they returned home from church on Oct. 8, 1944. Watching as a truckload of soldiers stopped outside their apartment building, “we all thought they were off to the front and people saluted them,” Wise told an interviewer years later. “But they weren’t going to the front. They had come to pick up a 10-year-old and a 13-year-old child.”

The sisters were interrogated about their identity and beaten before they were taken to the Sered concentration camp in Slovakia and then to Auschwitz. Describing the interminable train ride, Wise told Yad Vashem that people died standing up; the cattle car was packed so tightly with human life that even the dead could not rest on the ground.

Upon their arrival at Auschwitz, an adult hoisted Marta to the tiny window at the top of the train car and asked what she saw. “A lot of smoke in the air,” she replied, her first sight of the camp’s crematorium.

Marta and Eva were at first separated in the selection line, with Eva chosen for work and Marta directed toward the gas chambers, according to a published account of their story. A flyover by a Soviet airplane caused a stir of commotion on the ground, allowing the girls to be reunited.

They spent their imprisonment largely together. “I was ‘lucky,’ under the circumstances – I was lucky that the madman allowed me to be near my sister the whole time,” Wise told Yad Vashem, referring to Mengele.

Marta and Eva were placed together in a block with twins and dwarfs, many of them personally selected by Mengele for his sadistic and often fatal studies. Both Marta and Eva underwent medical experiments, although they never learned precisely what kind; Wise recalled only blood draws and injections that brought on agonizing stomachaches.

“I don’t remember the details,” she told Yad Vashem. “I just remember the pain, and I remember the injections. I remember him coming, and then you wanted to die anyway as soon as you saw him.”

Through their imprisonment, “amongst all this death, and horror, and torture, and murder,” Wise said, it never occurred to her or her sister that their parents would not be waiting for them at home when liberation came, or that life would not be the same when they returned.

“That’s how people survived, by believing that they will find their families when it’s all over,” she told Yad Vashem. “And that kept you going. Hope keeps you going.”

Wise’s younger sister Yehudit died in Auschwitz. Her other siblings and her parents survived the Holocaust. Their mother, Wise recalled, was “flabbergasted” when she and Eva appeared at their home in June 1945 after hitchhiking their way back to Bratislava.

“I don’t think she recognized us, really,” Wise said. “It’s beyond words to describe what you felt like when you got back.” But the joy of their reunion was tempered by yet another separation: Marta and Eva were both sick with tuberculosis, a highly infectious disease that was rampant in the camps, and they could not remain at home until they had recovered.

As the sisters grew up, Wise said, they told their parents nothing of their experience at Auschwitz. “We didn’t have the heart to tell them such a thing,” she said.

In 1948, the family immigrated to Australia, where Marta studied history at the University of Melbourne. In 1957, she married Harold Wise. They lived in Australia before settling in Israel in the late 1990s.

Wise’s survivors include her husband; their three daughters, Michelle Shir, Judy Joss and Miriam Bruce; and many grandchildren and great-grandchildren. Wise’s sister Eva Slonim, the author of the memoir “Gazing at the Stars: Memories of a Child Survivor,” is 91 and lives in Melbourne.

“I don’t know how we survived, how any single person survived in that climate,” Wise told the Associated Press. “That is a miracle to me. … And why I survived and others didn’t I don’t know. I am not God.”