Adam Walsh was 6 years old when he went missing from a Sears in Hollywood, Fla., on July 27, 1981. He had been playing video games at the store, but was not there when his mother returned. Tragically, his head — but not his body — was found a couple of weeks later in Vero Beach, Fla.

Wanting to do something about the death of his son, John Walsh became a victim’s advocate, gaining subsequent notoriety as the host of “America’s Most Wanted” and as a supporter of national legislation on child safety.