how did casper die

Casper the Friendly Ghost died from pneumonia after playing outside in the cold for too long, catching a severe cold that developed into pneumonia. He was just 12 years old when he died. This backstory was notably revealed in the 1995 live-action film "Casper," where it is shown that Casper's father, a mad scientist named J.T. McFadden, was devastated by his son's death and invented a machine called the Lazarus to try to bring Casper back to life. However, the attempt was unsuccessful, and Casper remained a ghost haunting his family home.