Born at Parramatta on 7 June 1883, he was the oldest surviving child of Claudius Beresford Cairnes (1840–1910), manager of the local branch of the Bank of New South Wales, and his wife, Elizabeth (Lizzie) Adams Cairnes, nee Rouse (1845–1930). After leaving The King’s School, Parramatta, Charlie served during the Second Anglo-Boer War with Kitchener’s Horse. In January 1902 he joined the 3rd New South Wales Imperial Bushmen, a regiment raised in South Africa, and was soon promoted to sergeant. Returning to Australia, Charlie joined the Colonial Sugar Refining Company as an analytical chemist and worked for them in Fiji. In October 1915 he returned to Sydney and embarked for England on the same ship as his cousin Geoffrey Terry. Commissioned second lieutenant in the Royal Field Artillery in December, Charlie was drafted to France the following June with C Battery, 148th Brigade RFA, 30th Division. He survived the Somme offensive, in which hundreds of thousands of Allied troops perished, only to be killed in action at Arras on 22 April 1917. Charlie is remembered on war memorials in both Australia and Fiji. His Imperial War Graves Commission cemetery register entry reads ‘Native of Parramatta, New South Wales’.
Before he left Sydney, Charlie had made his will. He left £1000 each to his sisters, Mary and Dora, while the residue of his estate – almost £3000 – went to his younger brother, Beresford Henry (1886–1930). Beresford had enlisted in the Australian Imperial Force in September 1914 and served as a gunner in the 1st Field Artillery Brigade on the Gallipoli Peninsula, where he was wounded in July 1915 and evacuated to a Cairo hospital. In May 1916 he was promoted to second lieutenant and sent to France, where he rose to lieutenant in August, and temporary captain in October 1917. Beresford was awarded the Military Cross in June 1918 for ‘consistent gallantry and keen devotion to duty and excellent services’ near Zonnebeke, east of Ypres, while in command of a Heavy Trench Mortar Battery, with special reference to operations when ammunition had to be transported over 2000 yards under heavy shellfire – a task he achieved despite the loss of six men. His recommendation made particular mention that ‘His consistent cheerfulness and courage have at all times set a most excellent example to his men’.