Captain Henry Telford Maffett and his sister Emilie Harmsworth were the two youngest children of William Hamilton Maffett (1817-1903), a barrister, and Marcella Bayly (1830-1913), St. Helena, Finglas, County Dublin. Emilie married her cousin Cecil Bishopp Harmsworth, 1st Baron Harmsworth, in 1897. Captain Henry Telford Maffett joined the Leinster Regiment, in 1894, and was killed on 20 October 1914 in the Battle of Armentières, France, during the First World War. He was shot at a forward observation post and his body was found and buried by a German lieutenant, Walther Reinhardt, who returned Maffett's personal effects to Emilie Harmsworth. Reinhardt then wrote about his experiences of the Western Front in a book called "Sechs monate Westfront: Feldzugserlebnisse eines Artillerie-Offiziers in Belgien, Flandern und der Champagne" [Six months on the Western Front: The Campaign Experiences of an Artillery Officer in Belgium, Flanders and Champagne] (published by Ernst Siegfried Mittler & Son, Berlin, 1915). In this book he mentions his discovery of Captain Maffett's body.