Biography
Margaret Cavendish Harley was born 11 February 1715 in Welbeck Abbey, Nottinghamshire, England, United Kingdom to Edward Harley, 2nd Earl of Oxford and Earl Mortimer (1689-1741) and Henrietta Cavendish Holles (1694-1755) and died 17 July 1785 Bulstrode, Buckinghamshire, England, United Kingdom of unspecified causes. She married William Bentinck, 2nd Duke of Portland (1709-1762) 11 July 1734 Oxford Chapel in Marylebone, Middlesex, England, United Kingdom.
Children
| Name | Birth | Death | Joined with |
| Elizabeth Cavendish-Bentinck (1735-1825) | 27 July 1735 | 12 December 1825 Lower Grosvenor Street, London, Greater London, England, United Kingdom | Thomas Thynne, 1st Marquess of Bath (1734-1796) |
| Henrietta Cavendish-Bentinck (1737-1827) | 8 February 1737 | 4 June 1827 | George Harry Grey, 5th Earl of Stamford (1737-1819) |
| William Henry Bentinck, 3rd Duke of Portland (1738-1809) | 14 April 1738 Welbeck Abbey, Nottinghamshire, England, United Kingdom | 30 October 1809 Bulstrode Park, Buckinghamshire, England, United Kingdom | Dorothy Cavendish (1750-1794) |
| Margaret Bentinck (1739-1756) | |||
| Frances Bentinck (1741-1743) | |||
| Edward Charles Bentinck (1744-1819) | |||
Footnotes (including sources)
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