Son of William Reierson Arbuthnot (1826-1913). Married Janet Elspeth Wemyss. Kenneth was educated privately, then at Bath College, then at RMA, Sandhurst; he had served with the Seaforth Highlanders since 1893, fighting in the Chitral expedition in 1895, in the Mahdist War in the Sudan in 1898 (including the Battle of Omdurman), and in the Second Boer War from 1900 to 1902. He was brigade major of the Gordon Infantry Brigade. He was killed in action in the Second Battle of Ypres in 1915.
|Offspring of Kenneth Wyndham Arbuthnot (1873-1915) and Janet Elspeth Sinclair-Wemyss (1889-1982)|
|John Sinclair-Wemyss Arbuthnot (1912-1992)||11 February 1912 Powys House, Kittybrewster, City of Aberdeen, Scotland, United Kingdom||13 June 1992 Worlington, Suffolk, England, United Kingdom|| (Margaret) Jean Duff (1919)|
|Robert Michael Wemyss Arbuthnot (1914-1946)|