Sydney Cyril O'Shannassy (SN 6576) was an 18 year old labourer from Ballarat when he enlisted there on June 28th 1916. He was assigned to the 8th Infantry Battalion and embarked from Melbourne in October on board the Nestor. He arrived in France in April 1917 and had several stays in hospital over the next year for comparatively minor ailments. On August 9th 1918 he was killed in action at Lihons. He has no known grave, and his name is recorded on the Australian Memorial at Villers-Bretonneux, France.

His brother Richard was killed at Gallipoli in 1915 and is also honoured with a tree in the Avenue.

Lucas’s Staffs Appreciation of Brave Men, the original Avenue register, records his name as Sydney C. O'Shanessey.