Sidney was born in April 1923 in Mile End, London to Barnett and Polish born Augusta nee Lustgarten and had an older brother Judah and a younger sister Rene. Sidney’s paternal family originated from Poland and their surname was Nacovitch. They became naturalised British citizens in 1904 and changed their surname by deed poll in 1941 to Newton.

Sidney enlisted on 19 February 1942, and saw service in Southern Rhodesia, Egypt, Palestine and India. He was a pilot, flew reconnaissance missions and delivered planes to where they were needed. Whilst in India, Sidney was attached to the 9 Ferry Unit. He died on 27 July 1945, aged 23 years, in Madras when his aircraft Thunderbolt KL255 crashed. Sidney was initially buried in the local cemetery at Vizagapatam and after the war he was reburied in the Madras War cemetery.

He attended the Harrow Synagogue and is remembered on their Memorial Board.