Mary Patricia Nevill, Marchioness of Abergavenny DCVO (20 October 1915^[1] – 22 February 2005) was a friend and Lady of the Bedchamber to Elizabeth II.

She was born Mary Patricia Harrison, the daughter of John Harrison of King’s Walden, and his wife, Hon. Margaret Harrison, a daughter of William Levy-Lawson, 3rd Baron Burnham.^[2]

On 4 January 1938, she married the John Nevill, Earl of Lewes, who inherited his father's title of Marquess of Abergavenny in 1954, whereupon Patricia became Marchioness of Abergavenny.^[2] They had five children:

• Lady Anne Patricia Nevill (b. 25 October 1938), married Captain Martin Whiteley and had issue.
• Lady Vivienne Margaret Nevill (15 February 1941 – 10 September 2018), married Alan Lillingston and had issue.
• Lady Jane Elizabeth Nevill (1944–1946), died in infancy.
• Henry John Montague Nevill, Earl of Lewes (1948–1965), educated at Eton, died without issue.^[3]
• Lady Rose Nevill (b. 15 July 1950); a bridesmaid at the wedding of Princess Margaret and Antony Armstrong-Jones. Lady Rose married George Clowes and had issue.

In 1960 it was suggested to her father (who lived at King's Walden and was a neighbour to the Strathmores' home of St. Paul's Walden Bury) that she become an Extra Lady of the Bedchamber to the Queen; and she held this position from 1960 to 1966. She then became a full Lady of the Bedchamber from 1966 until her retirement in 1987, when she reverted to an Extra Lady until her death.^[2]

The Marchioness of Abergavenny died on 22 February 2005, aged 89.^[4]

In 1970, Lady Abergavenny was appointed CVO and in 1981 DCVO. In 1969, she received the Grand Decoration in Gold with Star for Services to the Republic of Austria.^[5][6]