Sadako Sasaki was born on January 7, 1943, in the city of Hiroshima, Japan. She was two years old when the United States dropped an atomic bomb on Hiroshima on August 6, 1945, during World War II. The bomb killed an estimated 140,000 people, and Sadako was one of the many survivors who were exposed to radiation from the blast.

A few years later, in 1954, Sadako began experiencing symptoms of leukemia, a type of cancer that affects the blood-forming tissues of the body. She was admitted to the hospital and underwent a number of treatments, including radiation therapy and bone marrow transplants, but her condition continued to deteriorate.

During her time in the hospital, Sadako became fascinated by the art of origami, the Japanese tradition of paper folding. She began folding paper cranes, hoping to make a thousand of them, as it was said that anyone who did so would be granted a wish. Sadako believed that if she could make a thousand paper cranes, she would be able to recover from her illness.

Despite her best efforts, Sadako was unable to reach her goal of a thousand paper cranes. She passed away on October 25, 1955, at the age of 12.

After her death, Sadako's classmates and friends raised money to build a monument in her honor. The Children's Peace Monument, also known as the "Sadako Memorial," was erected in Hiroshima Peace Memorial Park in 1958. It features a statue of Sadako holding a golden crane and is inscribed with the words "This is our cry, This is our prayer, Peace in the world." The monument has become a symbol of peace and a reminder of the horrors of war.

Here are a few lesser-known facts about Sadako Sasaki:

Sadako's father, Shigeo Sasaki, was a tailor who owned a small shop in Hiroshima. After the bombing, he and his family fled the city and took refuge in the mountains.

Sadako's mother, Hisako Sasaki, was pregnant with her younger brother, Masahiro, at the time of the bombing. Masahiro was born a few months later and did not suffer any ill effects from the radiation.

Sadako was a talented runner and was a member of her school's track team. She was known for her speed and endurance, and often finished first in her races.

The story of Sadako and the thousand paper cranes has been widely popularized through the book "Sadako and the Thousand Paper Cranes," which was written by Eleanor Coerr and published in 1977. The book has been translated into many languages and has inspired numerous plays, films, and other works of art.

The Children's Peace Monument in Hiroshima is not the only monument dedicated to Sadako. There is also a statue of Sadako in Seattle, Washington, which was erected in 1977 by a group of Japanese-American students. The statue, which stands in a park near the Space Needle, is a replica of the one in Hiroshima and is inscribed with the words "This is our cry, This is our prayer, Peace in the world."