| | | | Baron Kerry, 1223 |
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| | | | Earl of Kerry, 1753 |
| | | | Thomas FitzMaurice 1668–1741 1st Earl of Kerry, 21st Baron Kerry |
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| | | | | | | | | Viscount FitzMaurice and Baron Dunkeron, 1751 Earl of Shelburne (2nd creation), 1753 Baron Wycombe, 1760 |
| | | | William FitzMaurice 1694–1747 2nd Earl of Kerry, 22nd Baron Kerry | | John Petty-Fitzmaurice 1706–1761 1st Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe |
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| | | | | | | | | Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 1784 |
| | | | Francis Thomas-Fitzmaurice 1740–1818 3rd Earl of Kerry, 23rd Baron Kerry | | William Petty-Fitzmaurice 1737–1805 1st Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 2nd Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe | | | | | | Baron Nairne |
| | | | | | | | | | | | | Baron Keith (1st creation: Ireland), 1797 Baron Keith (2nd creation: UK), 1801 Baron Keith (3rd creation: UK), 1803 Viscount Keith (UK), 1814 | | | | | |
| | | | | | | | John Henry Petty 1765–1809 2nd Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 3rd Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe | | George Keith Elphinstone 1746–1823 Viscount Keith, Baron Keith (Ire, UK, UK) | | Jane Mercer | | |
| | | | | | | | | | | | | Viscountcy Keith and Barony Keith (1st creation) extinct, 1801 | | | |
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| | | | | | | | Henry Petty-Fitzmaurice 1780–1863 3rd Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 4th Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe 4th Earl of Kerry, 24th Baron Kerry | | Margaret Mercer Elphinstone 1788–1867 Comtesse de Flahaut, 2nd Baroness Keith (Ire, UK), 7th Lady Nairne |
| | | | | | | | | | | | | Baronies Keith (2nd & 3rd creations) extinct, 1867 |
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| | | | | | | | Henry Thomas Petty-Fitzmaurice 1816–1866 4th Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 5th Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe 5th Earl of Kerry, 24th Baron Kerry | | Emily Jane Petty-FitzMaurice 1819–1895 8th Lady Nairne | | |
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Baron Mersey, 1910 Viscount Mersey, 1916 | | | | | | | | | | | | | | | Baron Fitzmaurice, 1906 |
John Charles Bigham 1840–1929 1st Viscount Mersey | | | | | | Henry Charles Keith Petty-Fitzmaurice 1845–1927 5th Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 6th Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe, 6th Earl of Kerry, 24th Baron Kerry, 9th Lord Nairne | | | | | | Edmond Fitzmaurice 1846–1935 Baron Fitzmaurice |
| | | | | | | | | | | | | | | | | | | Barony Fitzmaurice extinct, 1935 | | | | | |
Charles Clive Bigham 1872–1956 2nd Viscount Mersey | | | | | | Henry William Edmund Petty-Fitzmaurice 1872–1936 6th Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 7th Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe, 7th Earl of Kerry, 25th Baron Kerry, 10th Lord Nairne | | Charles Fitzmaurice 1874–1914 |
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Edward Clive Bigham 1906–1979 3rd Viscount Mersey | | Katherine Bigham 1912–1995 12th Lady Nairne | | Charles Hope Petty-Fitzmaurice 1917–1944 7th Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 8th Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe, 8th Earl of Kerry, 26th Baron Kerry, 11th Lord Nairne | | George John Charles Mercer Nairne Petty-Fitzmaurice 1912–1999 8th Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 9th Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe, 9th Earl of Kerry, 27th Baron Kerry | | |
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Richard Maurice Clive Bigham 1934–2006 4th Viscount Mersey, 13th Lord Nairne | | David Edward Hugh Bigham b. 1938 Heir apparent to the Viscountcy Mersey | | | | | | Charles Maurice Petty-Fitzmaurice b. 1941 9th Marquess of Lansdowne, Earl of Wycombe, and Viscount Calne and Calston, 10th Earl of Shelburne, Viscount FitzMaurice, Baron Dunkeron, and Baron Wycombe, 10th Earl of Kerry, 28th Baron Kerry |
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Edward John Hallam Bigham b. 1966 5th Viscount Mersey, 14th Lord Nairne | | Charles Richard Petty Bigham b. 1967 Heir apparent in the heir presumptive to the Viscountcy Mersey | | | | | | Simon Henry George Petty-Fitzmaurice b. 1970 styled Earl of Kerry |
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Flora Bigham, Mistress of Nairne b. 2003 styled Mistress of Nairne | | | | | | | | | | George Henry Charles Petty-Fitzmaurice b. 2020 styled Viscount Calne and Calston |
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