Eldest daughter of Philip Dauncey K.C. (1759–1819) and his wife Marie (Mary) (1769–1804), daughter of Elizabeth Dolignon, who had acted in loco parentis during Southey’s time at Westminster School. Louisa married Robert Bill, an admirer of Southey’s poetry, in 1820. As Southey had known both her parents, in 1819 he wrote to her, commiserating on the death of her father, which he had read about in the newspapers.