In 1973, Kirk publicly came out as gay during an interview. Kirk played in a slew of other films in the 1960s including 'The Absent-Minded Professor' and its sequel 'Son of Flubber.' He also starred in 'The Misadventures of Merlin Jones.' He played the middle son alongside James MacArthur and Kevin Corcoran - who played his brothers - in the 1960 film 'Swiss Family Robinson.' In 'The Shaggy Dog,' Kirk portrayed a teenage boy who was cursed with occasionally turning into a sheepdog. His big break came when he starred as Travis Coates in the 1957 film 'Old Yeller,' a story about a teenage boy and his heroic yellow dog.
Kirk started his career with several television shows including the Mickey Mouse Club's serialized adventure 'The Hardy Boys: The Mystery of the Applegate Treasure' and 'The Hardy Boys: The Mystery of the Ghost Farm,' which aired in 1956-1957. 'He made some wonderful films back in the day. 'He was very much a part of our kid star community,' Peterson said.