The only child of George and Barbara Seton and a cousin of Agnes (1764–1852; DNB) and Mary (1763–1852; DNB) Berry, friends of Horace Walpole (1717–1797; DNB). In 1807, she married the Revd James Bannister, Rector of Iddesleigh. Her date of death is unknown, but she is said to have been living in Honiton, Devon in 1838. Seton met Southey during his second visit to Portugal in 1800–1801, and corresponded with him until 1810. She was on very good terms with both Southey and his wife.