On 06 Nov 1895 [his father] Charles Richard John Spencer-Churchill 9th Duke Marlborough (age 23) and [his mother] Consuelo Vanderbilt Duchess Marlborough (age 18) were married at St Thomas' Church New York. She by marriage Duchess Marlborough. The marriage arranged by Mary "Minnie" Fiske Stevens (age 42) and encouraged by mother [his grandmother] Alva Erskine Smith (age 42). The marriage was unhappy; they seperated in 1906 and the mariage was annulled on 19 Aug 1926. He the son of George Charles Spencer-Churchill 8th Duke Marlborough and Albertha Frances Anne Hamilton Duchess Marlborough (age 48). He a great x 5 grandson of King Charles II of England Scotland and Ireland.

In 1916 Arthur Robert Mills 3rd Baron Hillingdon (age 24) and [his future sister-in-law] Edith Mary Cadogan Baroness Fitzwalter (age 21) were married.

In 1917 Edward Montagu Cavendish Stanley (age 22) and [his future sister-in-law] Sibyl Louise Beatrix Cadogan (age 24) were married. He the son of Edward George Villiers Stanley 17th Earl of Derby (age 51) and Alice Maude Olivia Montagu Countess Derby (age 54). They were third cousins.

On 02 Oct 1917 Humphrey Edmund de Trafford 4th Baronet (age 25) and [his future sister-in-law] Cynthia Hilda Evelyn Cadogan (age 21) were married.

On 17 Feb 1920 John Albert William Spencer-Churchill 10th Duke Marlborough (age 22) and Alexandra Mary Cadogan Duchess Marlborough (age 19) were married at St Margaret's Church, Westminster [Map]. He the son of Charles Richard John Spencer-Churchill 9th Duke Marlborough (age 48) and Consuelo Vanderbilt Duchess Marlborough (age 42).

In 1921 [his father] Charles Richard John Spencer-Churchill 9th Duke Marlborough (age 49) and [his step-mother] Gladys Marie Deacon Duchess Marlborough (age 39) were married; she had previoiusly been his mistress. She by marriage Duchess Marlborough. He the son of George Charles Spencer-Churchill 8th Duke Marlborough and Albertha Frances Anne Hamilton Duchess Marlborough (age 74). He a great x 5 grandson of King Charles II of England Scotland and Ireland.

On 14 Nov 1933 Walter Francis David Long (age 22) and [his future wife] Frances Laura Charteris Duchess Marlborough (age 18) were married at St Margaret's Church, Westminster [Map].

On 23 Feb 1943 William Humble Eric Ward 3rd Earl of Dudley (age 49) and [his future wife] Frances Laura Charteris Duchess Marlborough (age 27) were married. She by marriage Countess of Dudley of Dudley Castle in Staffordshire. The difference in their ages was 21 years. He the son of William Humble Ward 2nd Earl of Dudley.

On 05 Dec 1946 [his son-in-law] Major Charles Huguenot Waterhouse (age 28) and [his daughter] Caroline Spencer-Churchill (age 23) were married. She the daughter of John Albert William Spencer-Churchill 10th Duke Marlborough (age 49) and Alexandra Mary Cadogan Duchess Marlborough (age 46).

On 19 Oct 1951 [his son] John Spencer-Churchill 11th Duke of Marlborough (age 25) and [his daughter-in-law] Susan Mary Hornby (age 22) were married. He the son of John Albert William Spencer-Churchill 10th Duke Marlborough (age 54) and Alexandra Mary Cadogan Duchess Marlborough (age 51).

On 13 Jun 1960 Michael Temple Canfield (age 33) and [his future wife] Frances Laura Charteris Duchess Marlborough (age 44) were married. He the illegitmate son of Prince George Windsor 1st Duke Kent and Alice "Kiki" Preston aka Gwynne. He a grandson of George V King United Kingdom.

In 1961 [his son] John Spencer-Churchill 11th Duke of Marlborough (age 34) and [his daughter-in-law] Susan Mary Hornby (age 32) were divorced.

On 26 Jan 1972 John Albert William Spencer-Churchill 10th Duke Marlborough (age 74) and Frances Laura Charteris Duchess Marlborough (age 56) were married. She by marriage Duchess Marlborough. He the son of Charles Richard John Spencer-Churchill 9th Duke Marlborough and Consuelo Vanderbilt Duchess Marlborough.