In London, she met Thomas Anthony Trollope, a barrister, and at the age of 30, married him on 23 May 1809 in Heckfield, Hampshire. They had four sons and three daughters: Thomas Adolphus, Henry, Arthur, Emily (who died in a day), Anthony, Cecilia and Emily. When the Trollopes moved to a leased farm at Harrow-on-the-Hill in 1817, they faced financial struggles for lack of agricultural expertise. This was where Frances gave birth to her last two children. Two of her sons also became writers. Her eldest surviving son, Thomas Adolphus Trollope, wrote mostly histories: "The Girlhood of Catherine de Medici", "History of Florence", "What I Remember", "Life of Pius IX", and some novels. Her fourth son Anthony Trollope became a well-known and received novelist, establishing a strong reputation, especially for his serial novels, such as those set in the fictional county of Barsetshire, and his political series the Palliser novels. Despite producing six living children, their marriage was reputedly unhappy.