William Petty (26 May 1623 - 16 December 1687) - could you call him an "economist"?
In 1667 he married Elizabeth Waller (it was her second marriage; she had been married before with Sir Maurice Fenton). She became 1st Baroness of Shelburne (died c. 1708). They had three children:
- Charles Petty, 1st Baron Shelburne (no article - only a redir to Earl of Shelburne) -> no children
- Henry Petty, 1st Earl of Shelburne -> no children
- Anne, who married Thomas Fitzmaurice, 1st Earl of Kerry.
- The Shelburne title passed to Anne's son: John Petty, 1st Earl of Shelburne, who took his mother's surname, and whose descendants hold the title Marquis of Lansdowne.
- Her grandson William Petty, 2nd Earl of Shelburne, praised her as a woman of strong character and intelligence, the only person who could manage her bad-tempered and tyrannical husband.
- The Shelburne title passed to Anne's son: John Petty, 1st Earl of Shelburne, who took his mother's surname, and whose descendants hold the title Marquis of Lansdowne.
So William Petty was the great-grandfather of Prime Minister William Petty Fitzmaurice, 2nd Earl of Shelburne and 1st Marquess of Lansdowne (2 May 1737 – 7 May 1805).
the text in DNB (1896) about William Petty is from s:Author:Edmond_George_Fitzmaurice (also: Edmond George Petty-Fitzmaurice) (1846 - 1935). See: Edmond_Fitzmaurice,_1st_Baron_Fitzmaurice (19 June 1846 – 21 June 1935). He also wrote a book (?) on William Petty: The Life of Sir William Petty, 1623-1687 (1895)[1]