Louisa Fanny Hanson was the mother of JW's son Charles James Whistler Hanson. She was the daughter of Frances Hanson, née Raymond, and Henry Hanson, a groom. She was apparently a parlourmaid. Her address was 4 Grantley Villas, Lark Hall Rise, Clapham [#01953].
According to the Pennells, Louisa Hanson's son was adopted by JW's former mistress Joanna Hiffernan and went to stay with her at 5 Thistle Grove, despite the fact that JW had been unfaithful to her. Hiffernan continued to look after him as late as 1880 when JW was away in Venice with Maud Franklin, his current mistress.