| Honorific-Prefix: | The Honourable |
| Sonia Cubitt | |
| Birth Name: | Sonia Rosemary Keppel |
| Birth Date: | 24 May 1900 |
| Birth Place: | London, England, United Kingdom |
| Death Place: | Hampshire, England, United Kingdom |
| Children: | Rosalind Shand Henry Edward Cubitt, 4th Baron Ashcombe Jeremy Cubitt |
| Parents: | George Keppel (father) Alice Edmonstone (mother) |
| Relations: | Camilla, Queen of the United Kingdom (granddaughter) |
| Occupation: | Author |
Sonia Rosemary Cubitt, (née Keppel, previously The Hon. Mrs. Cubitt; 24 May 1900 – 16 August 1986) was a British socialite, author and aristocrat. She was the first wife of Roland Cubitt, 3rd Baron Ashcombe, and, through her only daughter Rosalind, was the maternal grandmother of Queen Camilla. Sonia is also known as the daughter of Alice Keppel, a mistress of King Edward VII.
Sonia Rosemary Keppel was born on 24 May 1900, as the youngest child of the Hon. George Keppel (1865–1947) and Alice Frederica Keppel (née Edmonstone; 1868–1947). Her mother was the youngest child of Sir William Edmonstone, 4th Baronet, while George was a son of William Keppel, 7th Earl of Albemarle, and his wife Sophia Mary Keppel (née MacNab). Sonia's mother Alice was a British society hostess and a long-time royal mistress of King Edward VII.
Sonia's only sibling was the English writer and socialite Violet Trefusis (née Keppel). Violet was known for her lesbian affair with writer Vita Sackville-West, who later became the lover of Virginia Woolf.
Sonia met her future husband, the Hon. Roland Calvert Cubitt, at the end of the First World War, shortly after the signing of the armistice in November 1918. Sonia was eighteen, Roland was nearing twenty and a young officer in the Coldstream Guards. He was the fourth of the six sons of Henry Cubitt, 2nd Baron Ashcombe; all three of his older brothers were killed in action during the First World War. Roland was heir to Ashcombe Barony and to a fortune established by his great-grandfather, Victorian builder Thomas Cubitt (1788–1855).
On 16 November 1920, Sonia and Roland married at the Guards Chapel of Wellington Barracks in London.
They had three children:
m. Virginia Carington (daughter of Peter Carington, 6th Baron Carrington)
m. Mary Elizabeth Dent-Brocklehurst (née Chipps) (widow of late Mark Dent-Brocklehurst)
The couple divorced on 4 July 1947, just a few months before Roland succeeded as the 3rd Baron Ashcombe. Hence Sonia was never styled Baroness Ashcombe. During her marriage she was styled the Hon. Mrs. Cubitt.
Sonia, like her sister Violet, was fond of writing. She wrote the books Three brothers at Havana, 1762 and The Sovereign Lady: A Life of Elizabeth Vassall, Third Lady Holland, with Her Family. She was appointed Officer, Order of the British Empire (O.B.E.) in 1959.
Sonia died on 16 August 1986 aged 86, after a long period of chronic osteoporosis. She was survived by her daughter Rosalind, elder son Henry and four grandchildren. Her younger son Jeremy predeceased her, dying at age 30 in 1958. Eight years later, in 1994, her daughter Rosalind also died from osteoporosis.[1]
Sonia's granddaughter, the future Queen Camilla, became a member of the National Osteoporosis Society (a charity dedicated to improving the diagnosis, prevention and treatment of osteoporosis) in 1994 to help raise awareness of the disease. Camilla became patron of the charity in 1997 and was appointed its president in 2001.[2]
In 1958, Sonia wrote her memoir titled Edwardian Daughter, in which she described what her childhood was like in the high-society of the Edwardian era. The memoir was dedicated to her daughter Rosalind.