Sarah Byng Osborn was born in Bedfordshire, England, the daughter of Admiral Sir George Byng, created 1st Viscount Torrington in 1721. In 1710, just shy of her 17th birthday, she married John Osborn of Chicksands Priory, also in Bedfordshire, with whom she had two sons. Her husband died nine years later, followed almost immediately by her younger son. Mrs. Osborn took on the management of her husband's property as well as his debts, and gave her surviving son Sir Danvers Osborn a greatly improved estate when he reached his majority. At age 60, she again took over Chicksands and became the guardian of her two grandsons after the death of Sir Danvers. She maintained a voluminous correspondence with family and friends, which was edited and published for the first time in 1890 by a descendant. The letters are valued by historians for their lively writing style, wealth of personal and domestic detail, observations on politics and social changes, and discussion of many prominent figures of Mrs. Osborn's era.