Margaret Bentinck, Duchess of Portland

Margaret Cavendish Bentinck, Duchess of Portland was a British aristocrat, styled Lady Margaret Harley before 1734, Duchess of Portland from 1734 to her husbands death in 1761, and Dowager Duchess of Portland from 1761 until her own death in 1785.

At 20, onJuly 1734, in Oxford Chapel, Marylebone, she married the 2nd Duke of Portland, her Sweet Will, and they later had six children

Source: Wikipedia