Alan was the elder son of Farquhar and Emma Kilminster of Inverell NSW. His birth was registered at Dundas NSW in 1899, before his parents moved to Inverell. Alan attended school at Inverell before going to Sydney Technical College and becoming an engineer’s apprentice at Shaw Engineering Works at Randwick NSW.
Alan was just eighteen when he enlisted in July 1917 and joined the 17th Battalion 21st Reinforcement. He left Australia on the troopship HMAT A14 Euripides in October. He was part of the Machine gun section serving in France when he was killed in action on 3 October 1918. Private Alan Kilminster has no known grave and his name is inscribed on the Australian National Memorial, at Villers-Bretonneux, France.
At Inverell Alan’s name is recorded on the town’s Honor Roll and Cenotaph and the Intermediate High School Honor Roll. In 1919 he was one of the men for whom a memorial tree was planted in Kurrajong Parade.