Hi Ray, thanks for info. I found the 1841 Ferrer record - Sudbury Hill House seems to be for the well-to-do: 1 governess and 7 servants. I can't work out his profession from the abbreviation. I've also found George Sydney Waterlow, living Sudbury House, 1890 Kelly's. He appears to be listed as a Middlesex magistrate. 1891 census gives a Thomas Darness, schoolmaster, living at Sudbury Hill House, again with 1 governess and 6 servants. I cant't find George Waterlow in 1891 census - perhaps he died and the house was then occupied by Darness (couldn't find his death on FreeBMD)? Unless there are 2 Sudbury houses, one with "Hill" and the other without. I found a third on 1862 Stanford map but this was in Hammersmith.
I couldn't work out your "follow the residences...John Brown". Nor why there might be a medical connection.
As for my ancestor, I don't know the profession of his father, but he did have his son educated at Harrow school, . lf the house in question was the rather grand Sudbury Hill one, perhaps his spouse to be was the daughter of a servant??? (names are Winkley and Chappell respectively)
Not sure this one is going anywhere fast....
Cheers,
Ray