John Henson was the son of puppeteer Jim Henson (1936-1990), best known as the creator of The Muppets, and Jane Henson (1934-2013), who assisted in the launch of the Muppets. He had four siblings: Lisa Henson (born 1960), Cheryl (born 1961), Brian (born 1963), and Heather (born 1970).
John performed Muppet character Sweetums starting in 1992 following the death of Richard Hunt (who trained John Henson in performing Sweetums). The role has since been passed to different puppeteers, including David Rudman, Noel MacNeal, Rob Mills and Matt Vogel. Vogel officially assumed the role in 2009.
Henson died of a heart attack on February 14, 2014, at age 48, at his home in Saugerties, New York. His family had a private funeral for him. He was cremated and his ashes were given to his family.