Who was Fanny Sitwell in Robert Louis Stevenson’s life?

Fanny Sitwell was an influential figure in the early life of Robert Louis Stevenson. They met in 1873 in Suffolk, England, through their mutual friend, the scholar Sidney Colvin, whom Sitwell later married.1

Described as a woman of charm and talent, Sitwell helped the young Stevenson gain confidence and express himself. Stevenson fell deeply in love with her, and in his letters to her, he adopted various roles, including those of a lover, a worshipper, and a son. One of the names he used for her in these letters, "Claire," eventually led to the incorrect historical assumption that he had an affair with a woman of that name. Over time, their romantic passion evolved into a lasting friendship.1