Sydney was born on 1 June 1920 in Hackney, London to Israel and Millie nee Cohen and had a younger brother David. Their father was a teacher with London County Council and in 1939 the family lived in Stansted Road, Bishops Stortford. Sydney was training to be a doctor and was listed as a medical student in 1939 before he enlisted in 1940. He was engaged to be married to Esther Dofsky.

Sydney was based at Bandoeng in the Dutch East Indies and was captured in the Battle of Java on 8 March 1942. He died at Hintok River Camp, Kanchanaburi in Thailand from amoebic dysentery a year later.