Called Maria, and appears in the Family Chronicle as Sylvia. She doesn't really emerge clearly either from the Chronicle, or from any subsequent history. All we really know is that she loved nature, and was very devout. She never married, and apparently spent her life doing good works for the church. From 1843 to around 1865 she lived at another house owned by the Grahams on the north side of Clapham Common. This house became known as The Grahams, from its close association with the Grahams and with Maria in particular38. She was instrumental in the building of St. George's church, Battersea, with its associated schools and vicarage. Quite a few of her letters survive, but, typically, I haven't yet managed to decipher them.

I don't know when she died, exactly. However, her will was proved at London, on 19 January 1875, and left 300 pounds to some trust supporting the Battersea church (A History of the County of Surrey, Vol. 4, Edited by H.E. Maiden, 1912.) so she must have died before then. Most likely close to that date.