On 07 Aug 1851 [her father] William Duncombe 1st Earl Feversham (age 22) and [her mother] Mabel Violet Graham Countess Feversham (age 18) were married. They were second cousins.
On 30 Mar 1864 Hermione Wilhelmina Duncombe Duchess Leinster was born to William Duncombe 1st Earl Feversham (age 35) and Mabel Violet Graham Countess Feversham (age 31). Coefficient of inbreeding 1.57%.
On 11 Feb 1867 [her grandfather] William Duncombe 2nd Baron Feversham (age 69) died. His son [her father] William Duncombe 1st Earl Feversham (age 38) succeeded 3rd Baron Feversham of Duncombe Park in Yorkshire. [her mother] Mabel Violet Graham Countess Feversham (age 33) by marriage Baroness Feversham Duncombe Park in Yorkshire.
In 1868 [her father] William Duncombe 1st Earl Feversham (age 38) was created 1st Earl Feversham. [her mother] Mabel Violet Graham Countess Feversham (age 34) by marriage Countess Feversham.
On 13 Apr 1880 [her future brother-in-law] Maurice Fitzgerald (age 27) and Adelaide Forbes (age 19) were married at Longford, County Longford. She the daughter of George Arthur Hastings Forbes 7th Earl Granard 1833-1889 (age 46). He the son of Charles William Fitzgerald Fitzgerald 4th Duke Leinster 1819-1887 (age 61) and Caroline Leveson-Gower Duchess Leinster 1827-1887 (age 52). He a great x 5 grandson of King Charles II of England Scotland and Ireland. 
On 02 May 1882 Charles John Oswald Fitzgerald (age 42) and [her future sister-in-law] Alice Fitzgerald (age 28) were married at Carton House, Carton, Kildare, County Kildare. She the daughter of Charles William Fitzgerald Fitzgerald 4th Duke Leinster 1819-1887 (age 63) and Caroline Leveson-Gower Duchess Leinster 1827-1887 (age 55). She a great x 5 granddaughter of King Charles II of England Scotland and Ireland.
On 17 Jan 1884 Gerald Fitzgerald 5th Duke Leinster 1851-1893 (age 32) and Hermione Wilhelmina Duncombe Duchess Leinster (age 19) were married. She the daughter of William Duncombe 1st Earl Feversham (age 54) and Mabel Violet Graham Countess Feversham (age 50). He the son of Charles William Fitzgerald Fitzgerald 4th Duke Leinster 1819-1887 (age 64) and Caroline Leveson-Gower Duchess Leinster 1827-1887 (age 56). He a great x 5 grandson of King Charles II of England Scotland and Ireland.
On 10 Feb 1887, coincidentally the same day his father died, 10 February, [her father-in-law] Charles William Fitzgerald Fitzgerald 4th Duke Leinster 1819-1887 (age 67) died at Carton House, Carton, Kildare, County Kildare. His son [her husband] Gerald Fitzgerald 5th Duke Leinster 1851-1893 (age 35) succeeded 5th Duke Leinster. Hermione Wilhelmina Duncombe Duchess Leinster (age 22) by marriage Duchess Leinster.
On 01 Mar 1887 [her son] Maurice Fitzgerald 6th Duke Leinster 1887-1922 was born to [her husband] Gerald Fitzgerald 5th Duke Leinster 1851-1893 (age 35) and Hermione Wilhelmina Duncombe Duchess Leinster (age 22) at Kilkea Castle, Castledermot, County Kildare.
On 21 Nov 1887 [her brother-in-law] Charles Fitzgerald (age 28) and Alice Sidonia Claudius were married at Calcutta. He the son of Charles William Fitzgerald Fitzgerald 4th Duke Leinster 1819-1887 and Caroline Leveson-Gower Duchess Leinster 1827-1887. He a great x 5 grandson of King Charles II of England Scotland and Ireland.
On 21 Sep 1888 [her son] Desmond Fitzgerald was born to [her husband] Gerald Fitzgerald 5th Duke Leinster 1851-1893 (age 37) and Hermione Wilhelmina Duncombe Duchess Leinster (age 24).
On 21 Jan 1891 [her brother-in-law] Henry Fitzgerald (age 27) and Inez Charlotte Grace Boteler were married at Taplow, Buckinghamshire [Map]. He the son of Charles William Fitzgerald Fitzgerald 4th Duke Leinster 1819-1887 and Caroline Leveson-Gower Duchess Leinster 1827-1887. He a great x 5 grandson of King Charles II of England Scotland and Ireland.
On 06 May 1892 [her son] Edward Fitzgerald 7th Duke Leinster 1892-1976 was born to [her husband] Gerald Fitzgerald 5th Duke Leinster 1851-1893 (age 40) and Hermione Wilhelmina Duncombe Duchess Leinster (age 28). His biological father was suspected to be Hugo Charteris 11th Earl Wemyss (age 34) with whom his mother was believed to have been having an affair at the time.
On 01 Dec 1893 [her husband] Gerald Fitzgerald 5th Duke Leinster 1851-1893 (age 42) died of typhoid. His son [her son] Maurice Fitzgerald 6th Duke Leinster 1887-1922 (age 6) succeeded 6th Duke Leinster.
On 19 Mar 1895 Hermione Wilhelmina Duncombe Duchess Leinster (age 30) died of tuberculosis at Menton.
Paternal Family Tree: Browne aka Duncombe
Maternal Family Tree: Elizabeth Helena MacDonnell 1747-1796
Kings Wessex: Great x 25 Grand Daughter of King Edmund "Ironside" I of England
Kings Gwynedd: Great x 22 Grand Daughter of Owain "Great" King Gwynedd 1100-1170
Kings Seisyllwg: Great x 28 Grand Daughter of Hywel "Dda aka Good" King Seisyllwg King Deheubarth
Kings Powys: Great x 23 Grand Daughter of Maredudd ap Bleddyn King Powys 1047-1132
Kings England: Great x 15 Grand Daughter of King Edward III of England
Kings Scotland: Great x 18 Grand Daughter of Robert "The Bruce" I King Scotland
Kings Franks: Great x 21 Grand Daughter of Louis VII King Franks
Kings France: Great x 17 Grand Daughter of Philip "The Fair" IV King France
Great x 4 Grandfather: Thomas Browne
Great x 3 Grandfather: Thomas Duncombe
Great x 4 Grandmother: Ursula Duncombe
Great x 2 Grandfather: Charles Slingsby Duncombe 11 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: Thomas Slingsby 4th Baronet 9 x Great Grand Son of King Edward III of England
Great x 3 Grandmother: Sarah Slingsby 10 x Great Grand Daughter of King Edward III of England
Great x 4 Grandmother: Sarah or Susan Savile
Great x 1 Grandfather: Charles Duncombe 1st Baron Feversham 12 x Great Grand Son of King Edward III of England
GrandFather: William Duncombe 2nd Baron Feversham 13 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: William Legge 1st Earl Dartmouth
Great x 3 Grandfather: George Legge 12 x Great Grand Son of King Edward III of England
Great x 4 Grandmother: Anne Finch Countess Dartmouth -1751
11 x Great Grand Daughter of King Edward III of England
Great x 2 Grandfather: William Legge 2nd Earl Dartmouth 13 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: Arthur Kaye 3rd Baronet
Great x 3 Grandmother: Elizabeth Kaye Baroness North and Guildford
Great x 1 Grandmother: Charlotte Legge Baroness Feversham Duncombe Park 14 x Great Grand Daughter of King Edward III of England
Father: William Duncombe 1st Earl Feversham 14 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: James Stewart 5th Earl Galloway 1670-1746
10 x Great Grand Son of King Edward III of England
Great x 3 Grandfather: Alexander Stewart 6th Earl Galloway 11 x Great Grand Son of King Edward III of England
Great x 4 Grandmother: Catherine Montgomerie Countess Galloway 11 x Great Grand Daughter of King Edward III of England
Great x 2 Grandfather: John Stewart 7th Earl Galloway 1736-1806 12 x Great Grand Son of King Edward III of England
Great x 1 Grandfather: George Stewart 8th Earl Galloway 1768-1834 13 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: Robert Dashwood
Great x 3 Grandfather: James Dashwood 2nd Baronet
Great x 4 Grandmother: Dorothy Reade
Great x 2 Grandmother: Anne Dashwood Countess Galloway 1743-1830
Great x 4 Grandfather: Edward Spencer
Great x 3 Grandmother: Elizabeth Spencer Lady Dashwood
GrandMother: Louisa Stewart Baroness Feversham Duncombe Park 14 x Great Grand Daughter of King Edward III of England
Great x 4 Grandfather: Edward Bayly 1st Baronet
Great x 3 Grandfather: Nicholas Bayly 2nd Baronet Bayly of Plas Newydd in Anglesey
Great x 2 Grandfather: Henry Bayly-Paget 1st Earl Uxbridge 12 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: Thomas Paget
10 x Great Grand Son of King Edward III of England
Great x 3 Grandmother: Caroline Paget Lady Plas Newydd Anglesey 11 x Great Grand Daughter of King Edward III of England
Great x 1 Grandmother: Jane Paget Countess Galloway 1774-1842 13 x Great Grand Daughter of King Edward III of England
Hermione Wilhelmina Duncombe Duchess Leinster 1864-1895 15 x Great Grand Daughter of King Edward III of England
Great x 4 Grandfather: George Graham 2nd Baronet
Great x 3 Grandfather: Very Reverend William Graham
Great x 2 Grandfather: Reverend Robert Graham
Great x 3 Grandmother: Mary Offley
Great x 1 Grandfather: James Graham 1st Baronet
GrandFather: James Graham 2nd Baronet 14 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: James Stewart 5th Earl Galloway 1670-1746 10 x Great Grand Son of King Edward III of England
Great x 3 Grandfather: Alexander Stewart 6th Earl Galloway 11 x Great Grand Son of King Edward III of England
Great x 4 Grandmother: Catherine Montgomerie Countess Galloway 11 x Great Grand Daughter of King Edward III of England
Great x 2 Grandfather: John Stewart 7th Earl Galloway 1736-1806 12 x Great Grand Son of King Edward III of England
Great x 1 Grandmother: Catherine Stewart Lady Graham 13 x Great Grand Daughter of King Edward III of England
Great x 4 Grandfather: Robert Dashwood
Great x 3 Grandfather: James Dashwood 2nd Baronet
Great x 4 Grandmother: Dorothy Reade
Great x 2 Grandmother: Anne Dashwood Countess Galloway 1743-1830
Great x 4 Grandfather: Edward Spencer
Great x 3 Grandmother: Elizabeth Spencer Lady Dashwood
Mother: Mabel Violet Graham Countess Feversham 15 x Great Grand Daughter of King Edward III of England
Great x 1 Grandfather: Colonel James Campbell of Ardkinglass
GrandMother: Frances "Fanny" Callander Lady Graham 20 x Great Grand Daughter of King John "Lackland" of England
Great x 2 Grandfather: 18 x Great Grand Son of King John "Lackland" of England
Great x 4 Grandfather: Clotworthy Skeffington 3rd Viscount Massereene
Great x 3 Grandmother: Rachel Skeffington Countess Antrim 17 x Great Grand Daughter of King John "Lackland" of England
Great x 4 Grandmother: Rachel Hungerford Viscountess Massereene
16 x Great Grand Daughter of King John "Lackland" of England
Great x 1 Grandmother: Elizabeth Helena MacDonnell 19 x Great Grand Daughter of King John "Lackland" of England