John (Jack) Alexander Young (SN 3739) was born in Melbourne but was working in Ballarat as a commercial traveller at the time of his enlistment on April 24th 1917. Only 18 years old and still living with his parents, he was posted to the 4th Light Horse Regiment, 29th Reinforcement, with which he embarked from Sydney aboard the Anchises in August. On arrival in England, he was trained as a gunner and was posted to France at the end of November, joining the 13th Field Artillery Brigade the following month. His service in France seems to have been relatively uneventful although he appears to have celebrated the war's impending end with some gusto, receiving a penalty of the loss of 14 days pay for "Drunkeness" and being "AWL - 3 parades" at the end of October, 1918. When the war ended, he was transferred back to England where he joined the Australian Army Pay Corps with which, at the end of 1919, he was promoted to the rank of Extra Regimental 2nd Corporal. The following year, he returned to Australia aboard the Ceramic, disembarking in Melbourne in April, and was discharged on July 25th 1920.

His older brother Bert also served in the AIF and is honoured with the neighbouring tree in the Avenue.