Identity:
Lady Louisa Isabella Mills, née Lascelles, eldest daughter of the 3rd Earl of Harewood, married Charles Mills, 1st Baron Hillingdon, in 1853.
Life:
Lady Mills may have known JW in the mid-seventies, when her name appears in an address book (#12714).
Bibliography:
Kelly's London Post Office Directory, London, 1861-62; Debrett's Peerage, Baronetage and Knightage, London, 1907.