The Court Circular shows on March 7 2014, The Duke Of York was represented by Princess Beatrice of York at the Funeral of the Lady Mary Clayton which was held in the Royal Chapel of All Saints, Windsor Great Park, HM the Queen, Prince Philip, and the Countess of Wessex were also in attendance.
The Lady Mary Cecilia Clayton née Leveson-Gower„ who died 13 February, 2014, aged 96, was a first cousin of Her Majesty the Queen and was a niece of the Queen Mother
She was born Mary Cecilia Leveson-Gower, 12 Dec, 1917, first child of the Hon William Spencer Leveson-Gower (1880-1953), a younger son of the 2nd Earl Granville (Peerage of the UK, cr 1833), by his wife the former Lady Rose Constance Bowes Lyon, GCVO (d 1967), an elder sister of HM Queen Elizabeth, consort of King George VI.
In 1939 her father succeeded his brother as 4th Earl Granville. The 4th Earl, KG, KCVO, was sometime Gov of N Ireland; Vice~Admiral. who was created KG in Dec, 1952., and who d. 25 June, 1953.
Lady Mary’s younger sibling was the late 5th Earl Granville
She married 7 July, 1956, Samuel Wittewronge Clayton, yr son of Brig-Gen Sir Gilbert Faliingham Clayton, KCMG, KBE, CB, by whom she had issue a son, Gilbert (b 1958), and a daughter Rose (1960).