From misterrogers.org:

We are very sorry to deliver the sad news that Fred Rogers died on February 27, 2003 after a brief battle with stomach cancer. We are grateful for the many people, young and old, who have cared about his work over the years and who continue to appreciate Mister Rogers’ Neighborhood on PBS. We hope that you’ll join us in celebrating his life by reflecting on his messages and taking them into your everyday lives.