According to CNN Robertson's widow Susan said the actor had been diagnosed with Stage 4 cancer last week while being treated for pneumonia at SMH. He was admitted to the hospital after his wife called for an ambulance because he was complaining of pain. Doctors initially diagnosed Robertson with pneumonia. However, further tests revealed he had lung cancer which had spread throughout his body to his brain, bones, liver and lymph nodes.
Before becoming an actor Robertson had been a decorated WWII soldier, a boxer and an avid horseman. Throughout his career he appeared in many movies and television shows often preferring and excelling in the Western genre. He is best remembered for his role as Wells Fargo agent Jim Hardie on the NBC/ABC series Tales Of Wells Fargo. Tales lasted from 1957-1962 and led to him garnering a lead role in the ABC series The Iron Horse.
His career spanned 45 years, from 1948-1993. He appeared in over 60 movie and television series. Among his many honors Robertson has a star on the Hollywood Walk Of Fame, received the Golden Boot Award in 1985, he is in the Hall of Great Western Performers and is an inductee in the Cowboy Hall of Fame in Oklahoma City.
Robertson was married several times and is survived by his wife of 33 years, Susan Robbins, and two children.