Kathleen married William John Robert Cavendish, Marquess of Hartington on 6 May 1944 in Register Office, Chelsea, Middlesex, England. William (son of Edward William Spencer Cavendish, 10th. Duke of Devonshire. KG. MBE. TD. and Lady Mary Alice Gascoyne-Cecil) was born on 10 Dec 1917 in St. George's, Hanover Sq. Middlesex, England; died on 10 Sep 1944 in Belgium; was buried in Leopoldsburgh War Cemetery, Limburg, Belgium. [Group Sheet]