 He served in the First AIF, and was killed in action on the first day of the Gallipoli Campaign.He was one of only two serving members of any Australian parliament to fall in World War I — the other, who fell at Gallipoli on 4 May 1915, was George Braund, also a New South Wales MLA.Larkin was born at North Lambton, New South Wales, to William Joseph Larkin, a quarryman and his wife Mary Ann, née Rennix.