Johnny Crawford, the original Mouseketeer who starred as the young son of the Civil War veteran portrayed by Chuck Connors on the 1958-63 ABC series The Rifleman, died Thursday, it was announced. He was 75. In 2019, it was revealed that Crawford had been diagnosed with Alzheimer's disease, and a GoFundMe campaign organized by Paul Petersen — the advocate for former child actors and onetime star of The Donna Reed Show — was set up to help the family deal with expenses. Crawford was 12 when he appeared for the first time as Mark McCain, son of the widower Lucas...