 Complete the following phrase:  He was born on 4 September 1880 to Sophia and Pascoe Du Pré Grenfell. He was one of fifteen children. He had a twin brother, Riversdale Grenfell, also in the 9th Lancers, who was killed in action in September 1914. Their maternal grandfather was Admiral John Pascoe Grenfell and other relatives included their uncle, Field Marshal Francis Grenfell, 1st Baron Grenfell. An older brother, Lieutet Robert Septimus Grenfell, 21st Empress of Indias Lancers, was killed in a cavalry charge during the Battle of Omdurman in 1898. Three other brothers, Cecil Grenfell, Howard Maxwell Grenfell and Arthur Morton Grenfell all reached the rank of Lieutet Colonel in the British Army. A cousin, Lieutet Claude George Grenfell Thorneycrofts Mounted Infantry was killed at 