Mary Grey, Countess Grey

Mary Elizabeth Grey, Countess Grey (née Ponsonby), was born on 4 March 1776 in Whitehaven. She was the only daughter of William Ponsonby (1744–1806), who later became the 1st Baron Ponsonby, and his wife, the Honourable Louisa Molesworth (1749–1824). Louisa was a daughter of Richard Molesworth, the 3rd Viscount Molesworth.

On 18 November 1794, she married Charles Grey, a Member of Parliament born in 1764, who later became the 2nd Earl Grey and served as Prime Minister of the United Kingdom from 22 November 1830 to 16 July 1834. Charles Grey was the son of Charles Grey (1729–1807), who was later created 1st Baron Grey and 1st Earl Grey, and his wife Elizabeth Grey (née Grey), who lived from 1743 to 1822.

Mary Elizabeth and Charles Grey had a total of fifteen children, comprising ten sons and five daughters. Their children included:

- Lady Louisa Elizabeth Grey (7 April 1797 – 26 November 1841), who married John Lambton, 1st Earl of Durham.

- Lady Elizabeth Grey (10 July 1798 – 8 November 1880), who married John Crocker Bulteel.

- Lady Caroline Grey (30 August 1799 – 28 April 1875), who married Captain The Hon. George Barrington.

- Lady Georgiana Grey (17 February 1801 – 13 September 1900), who did not marry.

- Henry George Grey, the 3rd Earl Grey (28 December 1802 – 9 October 1894), who became a politician.

- General Charles Grey (15 March 1804 – 31 March 1870), father of Albert Grey, 4th Earl Grey.

- Admiral Sir Frederick William Grey (23 August 1805 – 2 May 1878).

- Lady Mary Grey (2 May 1807 – 6 July 1884), who married Charles Wood, 1st Viscount Halifax.

- Hon. William Grey (13 May 1808 – 11 February 1815).

- Admiral Hon. George Grey (16 May 1809 – 3 October 1891), who married Jane Frances Stuart.

- Hon. Thomas Grey (29 December 1810 – 8 July 1826).

- Reverend Hon. John Grey MA, DD (2 March 1812 – 11 November 1895), who married Lady Georgiana Hervey, daughter of the Marquess of Bristol.

- Reverend Hon. Francis Richard Grey MA (31 March 1813 – 22 March 1890), who married Lady Elizabeth Howard.

- Hon. Henry Cavendish Grey (16 October 1814 – 5 September 1880).

- Hon. William George Grey (15 February 1819 – 19 December 1865), who married Theresa Catherine, daughter of a Swedish Count Stedink.

In addition to these living children, Mary Elizabeth Grey experienced the stillbirth of a daughter in 1796.

Charles Grey served as Prime Minister from November 1830 to July 1834. Following his death on 17 July 1845, Mary Elizabeth Grey was widowed. She died on 26 November 1861 at the age of 85 in Eaton Square, London.