John Oliver Kilby was a consultant surgeon in north Gloucestershire. He was born on 21 November 1933 in Brentford, Middlesex, the son of Bernard William Kilby and Ruth Emily Kilby née Howse. He studied medicine at Charing Cross Medical School and qualified in 1958. He gained his fellowship of the Royal College of Surgeons of England in 1962. He was a surgical registrar at Southmead Hospital in Bristol, a senior fellow in surgery at the University of Washington, USA, and a senior surgical registrar for the United Bristol Hospitals. From 1971 he was a consultant surgeon at Gloucester Royal Infirmary and later at Gloucester Royal Hospital. In 1966 he married Hilary Crampton. They had two sons, Graeme and Laurence. He died on 28 July 2015 at the age of 81.