1) Sadako was a talented runner who enjoyed participating in races, but began feeling dizzy and ill. She was diagnosed with leukemia, which she developed from radiation exposure due to the atomic bomb dropped on Hiroshima.
2) In the hospital, Sadako began folding origami cranes in hopes of making 1,000 to grant her wish to recover from her illness. She befriended another patient, Kenji, but he sadly passed away from his own leukemia.
3) Though Sadako folded over 600 cranes, her condition worsened and she grew very weak. She imagined her cranes flying away before she died at age 12 from atomic bomb disease. Sadako became a symbol of peace