A preliminary sketch for this miniature is illustrated in D. Foskett, op. cit., London, 1964, pl. XXXI, no. 76.
Miss Twining was one of the four daughters of Richard Twining (1749-1824), director of the East India Company and head of the tea business located in the Strand. He married Mary Aldred of Norwich in 1771 and had six sons and four daughters.