On 03 Dec 1946 [his father] Robert George Grosvenor 5th Duke Westminster 1910-1979 (age 36) and [his mother] Viola Maud Lyttelton Duchess Westminster 1912-1987 (age 34) were married. They were second cousins.
On 22 Dec 1951 Gerald Cavendish Grosvenor 6th Duke Westminster was born to Robert George Grosvenor 5th Duke Westminster 1910-1979 (age 41) and Viola Maud Lyttelton Duchess Westminster 1912-1987 (age 39). Coefficient of inbreeding 1.63%.
On 25 Feb 1967 [his uncle] Gerald Hugh Grosvenor 4th Duke Westminster 1907-1967 (age 60) died. His brother [his father] Robert George Grosvenor 5th Duke Westminster 1910-1979 (age 56) succeeded 5th Duke Westminster, 7th Marquess Westminster, 8th Earl Grosvenor, 14th Baronet Grosvenor of Eaton in Cheshire. [his mother] Viola Maud Lyttelton Duchess Westminster 1912-1987 (age 54) by marriage Duchess Westminster.
On 19 Feb 1979 [his father] Robert George Grosvenor 5th Duke Westminster 1910-1979 (age 68) died. His son Gerald Cavendish Grosvenor 6th Duke Westminster (age 27) succeeded 6th Duke Westminster, 8th Marquess Westminster, 9th Earl Grosvenor, 15th Baronet Grosvenor of Eaton in Cheshire.
On 03 May 1987 [his mother] Viola Maud Lyttelton Duchess Westminster 1912-1987 (age 74) died in a car accident at Dungannon, County Tyrone.
On 29 Jan 1991 [his son] Hugh Grosvenor 7th Duke of Westminster 1991- was born to Gerald Cavendish Grosvenor 6th Duke Westminster (age 39).
On 09 Aug 2016 Gerald Cavendish Grosvenor 6th Duke Westminster (age 64) died. His son [his son] Hugh Grosvenor 7th Duke of Westminster 1991- (age 25) succeeded 7th Duke Westminster, 9th Marquess Westminster, 10th Earl Grosvenor, 16th Baronet Grosvenor of Eaton in Cheshire.
Paternal Family Tree: Grosvenor
Kings Wessex: Great x 26 Grand Son of King Edmund "Ironside" I of England
Kings Gwynedd: Great x 22 Grand Son of Owain "Great" King Gwynedd 1100-1170
Kings Seisyllwg: Great x 28 Grand Son of Hywel "Dda aka Good" King Seisyllwg King Deheubarth
Kings Powys: Great x 23 Grand Son of Maredudd ap Bleddyn King Powys 1047-1132
Kings England: Great x 13 Grand Son of King Henry VII of England and Ireland
Kings Scotland: Great x 19 Grand Son of Robert "The Bruce" I King Scotland
Kings Franks: Great x 22 Grand Son of Louis VII King Franks
Kings France: Great x 16 Grand Son of Charles "Beloved Mad" VI King France
Great x 4 Grandfather: Richard Grosvenor 1st Earl Grosvenor
Great x 3 Grandfather: Robert Grosvenor 1st Marquess Westminster
Great x 2 Grandfather: Richard Grosvenor 2nd Marquess Westminster 1795-1869 13 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: Thomas Egerton 1st Earl Wilton
11 x Great Grand Son of King Edward III of England
Great x 3 Grandmother: Eleanor Egerton Marchioness Westminster 12 x Great Grand Daughter of King Edward III of England
Great x 1 Grandfather: Hugh Lupus Grosvenor 1st Duke Westminster 10 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandfather: Granville Leveson-Gower 1st Marquess Stafford 10 x Great Grand Son of King Edward III of England
Great x 3 Grandfather: George Granville Leveson-Gower 1st Duke Sutherland 8 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandmother: Louisa Egerton Countess Gower 1723-1761 7 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 2 Grandmother: Elizabeth Mary Leveson-Gower Marchioness Westminster 1797-1891 9 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandfather: William Sutherland 18th Earl Sutherland 1735-1766 8 x Great Grand Son of King Henry VII of England and Ireland
Great x 3 Grandmother: Elizabeth Sutherland Duchess Sutherland 19th Countess Sutherland 9 x Great Grand Daughter of King Henry VII of England and Ireland
GrandFather: Hugh William Grosvenor 11 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandfather: George Augustus Henry Cavendish 1st Earl Burlington 1754-1834
8 x Great Grand Son of King Henry VII of England and Ireland
Great x 3 Grandfather: Charles Compton Cavendish 1st Baron Chesham 9 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandmother: Elizabeth Compton Countess Burlington 1760-1835
12 x Great Grand Daughter of King Edward III of England
Great x 2 Grandfather: William George Cavendish 2nd Baron Chesham 10 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandfather: George Gordon 9th Marquess Huntly 1761-1853 12 x Great Grand Son of King Edward III of England
Great x 3 Grandmother: Catherine Susan Gordon Baroness Chesham 11 x Great Grand Daughter of King Edward IV of England
Great x 4 Grandmother: Catherine Anne Cope Marchioness Huntly 1771-1832 10 x Great Grand Daughter of King Edward IV of England
Great x 1 Grandmother: Katherine Cavendish Duchess Westminster 11 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandfather: Henry Lascelles 2nd Earl Harewood 1767-1841
Great x 3 Grandfather: William Lascelles
Great x 2 Grandmother: Henrietta Frances Lascelles Baroness Chesham 11 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandfather: George Howard 6th Earl Carlisle 1773-1848
9 x Great Grand Son of King Henry VII of England and Ireland
Great x 3 Grandmother: Caroline Georgiana Howard 10 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandmother: Georgiana Cavendish Countess Carlisle 1783-1858 9 x Great Grand Daughter of King Henry VII of England and Ireland
Father: Robert George Grosvenor 5th Duke Westminster 1910-1979 12 x Great Grand Son of King Henry VII of England and Ireland
Great x 3 Grandfather: John Crichton 13 x Great Grand Son of King Edward III of England
Great x 4 Grandmother: Mary Caroline Hervey Countess Erne 1753-1842
12 x Great Grand Daughter of King Edward III of England
Great x 2 Grandfather: 14 x Great Grand Son of King Edward III of England
Great x 1 Grandfather: 14 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: John Beresford
11 x Great Grand Son of King Edward III of England
Great x 3 Grandfather: Charles Cobbe Beresford 12 x Great Grand Son of King Edward III of England
Great x 4 Grandmother: Constantia Ligondes
Great x 2 Grandmother: Selina Griselda Beresford Countess Erne 1804-1884 13 x Great Grand Daughter of King Edward III of England
Great x 4 Grandfather: William Montgomery 1st Baronet
Great x 3 Grandmother: Amelia Montgomery
Great x 4 Grandmother: Anne Evatt
GrandMother: Mabel Florence Mary Creighton 15 x Great Grand Daughter of King Edward III of England
Gerald Cavendish Grosvenor 6th Duke Westminster 1951-2016 13 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandfather: William Henry Lyttelton 1st Baron Lyttelton 11 x Great Grand Son of King Edward III of England
Great x 3 Grandfather: William Henry Lyttelton 3rd Baron Lyttelton 12 x Great Grand Son of King Edward III of England
Great x 4 Grandmother: Caroline Bristow Baroness Lyttelton
Great x 2 Grandfather: George William Lyttelton 4th Baron Lyttelton 12 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandfather: George John Spencer 2nd Earl Spencer
10 x Great Grand Son of King Henry VII of England and Ireland
Great x 3 Grandmother: Sarah Spencer 11 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandmother: Lavinia Bingham Countess Spencer 1762-1831
Great x 1 Grandfather: Charles Lyttelton 8th Viscount Cobham 11 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandfather: Stephen Glynne 7th Baronet
Great x 3 Grandfather: Stephen Richard Glynne 8th Baronet
Great x 2 Grandmother: Mary Glynne Lady Lyttelton 10 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandfather: Richard Griffin 2nd Baron Braybrook
11 x Great Grand Son of King Edward III of England
Great x 3 Grandmother: Mary Griffin 9 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandmother: Catherine Granville Baroness Braybrook
8 x Great Grand Daughter of King Henry VII of England and Ireland
GrandFather: John Cavendish Lyttelton 9th Viscount Cobham 12 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandfather: George Augustus Henry Cavendish 1st Earl Burlington 1754-1834 8 x Great Grand Son of King Henry VII of England and Ireland
Great x 3 Grandfather: Charles Compton Cavendish 1st Baron Chesham 9 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandmother: Elizabeth Compton Countess Burlington 1760-1835 12 x Great Grand Daughter of King Edward III of England
Great x 2 Grandfather: William George Cavendish 2nd Baron Chesham 10 x Great Grand Son of King Henry VII of England and Ireland
Great x 4 Grandfather: George Gordon 9th Marquess Huntly 1761-1853 12 x Great Grand Son of King Edward III of England
Great x 3 Grandmother: Catherine Susan Gordon Baroness Chesham 11 x Great Grand Daughter of King Edward IV of England
Great x 4 Grandmother: Catherine Anne Cope Marchioness Huntly 1771-1832 10 x Great Grand Daughter of King Edward IV of England
Great x 1 Grandmother: Mary Susan Cavendish Viscountess Cobham 11 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandfather: Henry Lascelles 2nd Earl Harewood 1767-1841
Great x 3 Grandfather: William Lascelles
Great x 2 Grandmother: Henrietta Frances Lascelles Baroness Chesham 11 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandfather: George Howard 6th Earl Carlisle 1773-1848 9 x Great Grand Son of King Henry VII of England and Ireland
Great x 3 Grandmother: Caroline Georgiana Howard 10 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 4 Grandmother: Georgiana Cavendish Countess Carlisle 1783-1858 9 x Great Grand Daughter of King Henry VII of England and Ireland
Mother: Viola Maud Lyttelton Duchess Westminster 1912-1987 13 x Great Grand Daughter of King Henry VII of England and Ireland
Great x 1 Grandfather: Charles Leonard
GrandMother: Violet Leonard Viscountess Cobham