Sylvester was the son of John and Julia Forsyth of Bukkulla, north of Inverell. His birth was registered at Inverell in 1894. He was a twenty two year old Labourer when he enlisted at Inverell in September 1916. At the Dinton Vale Hall a farewell function was held for Sylvester during which he was presented with a wrist watch by residents and a gold inscribed medal by members of the Dinton Vale Rifle Club.
As a member of the 54th Battalion he sailed from Australia on HMAT A29 Suevic in November 1916, arriving in England at the end of January 1917. He was sent to France in April. Five months later he became ill and was returned to England where he was admitted to 1st Southern General Hospital at Birmingham. He remained in England until sent back to France in April 1918. Sylvester returned to Australia in August 1919 and was discharged the following month.
Upon his return he was given a Welcome Home at Bukkulla Hall and presented with a gold inscribed medal. In 1940 he married Lillie Hamel. After living most of his life at Bukkulla, Sylvester moved to Inverell where he died in 1972. His name is recorded on the Ashford Honor Roll.