Sadako Sasaki was just two years old and at home—about 1.6 kilometers (1 mile) from ground zero—when the United States dropped an atomic bomb on Hiroshima. She was blown out of the window but miraculously found alive, with no visible injuries. While fleeing the city, Sadako and her mother were caught in the black rain.
Despite the harsh post-war conditions, Sadako grew up healthy and strong. She became the top runner in her class. However, during winter break in 1955, she began experiencing a sore throat and swelling in her neck. In January, she was diagnosed with acute malignant lymph gland leukemia—a common illness among hibakusha (atomic bomb survivors) due to radiation exposure.​​​​​​​
She was admitted to the Hiroshima Red Cross Hospital. There, a friend told her the legend of the thousand paper cranes: that anyone who folds Senbazuru - 1,000 origami cranes - is granted a wish. Sadako began folding cranes using anything she could find—even medicine wrappings and scrap paper. She eventually reached her goal, but her health continued to decline.
On the morning of October 25, 1955, Sadako asked for tea over rice and thanked her family—those were her final words. She was just 12 years old.​​​​​​​
After her death, her classmates published a collection of letters to raise funds for a memorial honoring Sadako and all children who died from the atomic bomb. In 1958, the Children’s Peace Monument was unveiled in Hiroshima Peace Memorial Park. At its base is a plaque that reads:
“This is our cry. This is our prayer. Peace in the world.”