Childers was born at Cantley Hall near Doncaster, the eldest son by the second marriage of Childers Walbanke-Childers, who had assumed the latter name when he inherited the estates of his grandfather, Leonard Childers, of Carr House, Yorkshire. His great nephew, Hugh Childers would become First Lord of the Admiralty and Chancellor of the Exchequer.
He joined the 2nd West India Regiment as an ensign on 25 February 1799 before transferring to the 11th Light Dragoons as a cornet on 5 August in the same year. On 25 August 1801 he was promoted to Lieutenant; to Captain on 14 June 1805; to brevet Major on 25 August 1814 and to brevet Lieutenant-colonel on 18 June 1815, the day of the Battle of Waterloo on the orders of the Prince Regent for his conduct during the battle. He became a major in the 60th Regiment of Foot on 15 April 1819 before transferring back to the 11th Light Dragoons in the same rank on 24 June 1819. He was promoted to Lieutenant-colonel on 21 September 1820 and to brevet Colonel on 10 January 1837.
During the Peninsular War, Childers was present at the battles of El Bodón (September 1811), Morales (June 1813), the Combat of Castrejón (July 1812), the Battle of Salamanca (July 1812), the Battle of Venta del Pozo (October 1812) and the battles of Vitoria (June 1813, Tolosa (June 1813) and Bayonne.
In his journal of the war, fellow cavalry officer William Tomkinson wrote:
Captain Childers of the 11th was the officer who particularly exerted himself, to which the safety of the detachment is to be considerably ascribed. He charged bodies three times their number, rode at then with the greatest determination, and always succeeded."
- Canada, British Regimental Registers of Service, 1756–1900
- Dalton 1904, p. 18.
- Tomkinson 1894, p. 117.
- A near observer (1815). The Battle of Waterloo, containing the series of accounts published by authority, British and foreign [&c.]. p. 251.
- Bromley & Bromley 2015, p. 1822.
- Bromley & Bromley 2015, p. 1821.
- Bromley, Janet; Bromley, David (2015). Wellington's Men Remembered Volume 1: A Register of Memorials to Soldiers who Fought in the Peninsular War and at Waterloo- Volume I: A to L. Pen and Sword. ISBN 978-1-4738-5768-1.CS1 maint: ref=harv (link)
- Dalton, Charles (1904). The Waterloo roll call. With biographical notes and anecdotes. London: Eyre and Spottiswoode.CS1 maint: ref=harv (link)
- Tomkinson, William (1894). The Diary of a Cavalry Officer in the Peninsular and Waterloo Campaign, 1809-1815. S. Sonnenschein & Company.CS1 maint: ref=harv (link)