John Bennett was a member of a family with four generations of doctors. His grandfather, John Henry Bennett, a chemist in Terang, decided to do medicine in his fifties. He practised in Auburn. His father, Frederick John, after serving in the war (1914 to 1918), studied medicine at Melbourne University, and also practised in Auburn. John had his early education at Scotch College, Melbourne. In 1935, Dr Bennett, with his wife and family went to England. John continued his education at Mill Hill School, London, and then entered Saint Bartholomew's Hospital Medical School, graduating MB BS in 1947. He was house physician at Hammersmith from 1947 to 1948. The family returned to Australia in 1948, and John was a medical officer at Heidelberg (Repatriation) Hospital, from 1948 to 1953. John's younger brother, Bob, who qualified in Melbourne in 1950, practises as a radiologist – and is a most competent artist.

John was admitted MRACP in 1953. He then joined a group practice in Surrey Hills, but continued his interest in internal medicine as clinical assistant in the unit of the late Dr Bill King at the Royal Melbourne Hospital until 1965. He was held in very high esteem by his colleagues and his patients. John married Christine Hudson of Trumpington, Cambridge, in 1946, and they had three children. The second son graduated in medicine and practises in Hobart. Also, two nieces have graduated and continue the GP tradition of the family.

John was very interested in the outdoors; he enjoyed camping and fishing, and was a keen ornithologist. He always made his own trout flies with meticulous care and artistry. He became interested in the classical guitar, at which, with professional tutelage, he became proficient. He was a member of the Victorian Scottish Regiment, and its medical officer for many years.

John died suddenly at the age of 47 years, leaving his family, and many friends and patients completely stunned.