Barbazon (1st Earl of Bessborough) Ponsonby
- 1758(
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- 1 Barbazon (1st Earl of Bessborough) Ponsonby [1] d. 4 Jul 1758
- Sarah Margetson d. 21 May 1733
- 2 William (2nd Earl of Bessborough) Ponsonby [1.1] b. 1704 d. 11 Mar 1793
- Caroline (of Devonshire) Cavendish b. 22 May 1719 d. 20 Jan 1760
- 3 Frederich (3rd Earl of Bessborough) Ponsonby [1.1.1] b. 24 Jan 1758 d. 3 Feb 1844
- Henrietta Frances (Countess) Spencer d. 14 Nov 1821
- 4 John William (4th Earl of Bessborough) Ponsonby [1.1.1.1] b. 31 Aug 1781 d. 16 May 1847
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- 4 William Francis S (1st Lord Mauley) Ponsonby [1.1.1.2] b. 31 Jul 1787 d. 16 Jul 1855
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- 4 John William (4th Earl of Bessborough) Ponsonby [1.1.1.1]
- 3 Charlotte (of Bessborough) Ponsonby [1.1.2] d. Yes, date unknown
- William 4th Earl Fitzwilliam b. 30 May 1748 d. Yes, date unknown
- 4 Charles William W (5th Earl Fitzwilliam [1.1.2.1] d. Yes, date unknown
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- 4 Charles William W (5th Earl Fitzwilliam [1.1.2.1]
- 3 Catherine (of Bessborough) Ponsonby [1.1.3] d. 4 Sep 1789
- Aubrey (5th Duke of St Albans) Beauclerk b. 3 Jun 1740 d. 9 Feb 1802
- 4 Aubrey (6th Duke of St Albans) Beauclerk [1.1.3.1] b. 21 Aug 1765 d. 8 Dec 1815
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- 4 William (8th Duke of St Albans) Beauclerk [1.1.3.2] b. 18 Dec 1766 d. Yes, date unknown
- 4 Amelius Beauclerk [1.1.3.3] b. Aug 1771 d. Yes, date unknown
- 4 Frederick Beauclerk [1.1.3.4] b. 8 May 1773 d. Yes, date unknown
- 4 Catherine Elizabeth Beauclerk [1.1.3.5] d. Yes, date unknown
- 4 Georgina Beauclerk [1.1.3.6] d. Yes, date unknown
- 4 Caroline Beauclerk [1.1.3.7] d. 23 Nov 1838
- 4 Aubrey (6th Duke of St Albans) Beauclerk [1.1.3.1]
- 3 Frederich (3rd Earl of Bessborough) Ponsonby [1.1.1]
- 2 John (Rt Hon) Ponsonby [1.2] d. 12 Dec 1789
- Elizabeth (of Devonshire) Cavendish d. Yes, date unknown
- 3 William Brabazon (of Imokilly) 1st Baron Ponsonby [1.2.1] b. 15 Sep 1744 d. 5 Nov 1806
- Louisa Molesworth d. Yes, date unknown
- 4 John (of Imokilly) 2nd Baron Ponsonby [1.2.1.1] b. Abt 1770 d. Yes, date unknown
- 4 John (of Imokilly) 2nd Baron Ponsonby [1.2.1.1]
- 3 Frances Ponsonby [1.2.2] b. 18 Feb 1757 d. Yes, date unknown
- Cornelius (1st Baron Lismore Shanbally) O'callaghan b. 7 Jan 1740 d. 12 Jul 1797
- 4 Cornelius (1st Viscount Lismore) O'callaghan [1.2.2.1] b. 2 Oct 1775 d. Yes, date unknown
- 4 Louisa O'callaghan [1.2.2.2] d. 18 Apr 1863
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- 4 Cornelius (1st Viscount Lismore) O'callaghan [1.2.2.1]
- 3 William Brabazon (of Imokilly) 1st Baron Ponsonby [1.2.1]
- 2 William (2nd Earl of Bessborough) Ponsonby [1.1]