In the 1861 census for Bishopgate, London I have found Alfred (13), Guss (11) and William Fray (9)and visiting Thomas Blowers (41), a policeman, and his wife Maria (33). Thomas was born in Cambridgeshire. Maria's birth place is Somerset, as are the visiting children. I can find no trace of these children in Somerset. Births of children with these names do appear in London in the right years. Could they be the sons of Augustus and Caroline? was the death not Caroline daughter but Caroline his wife? I have tried to find births there are not that many 'Walls' so I did wonder if Freay and Walls were continental Frey and Walz. Since Augustus was a clockmaker perhaps Swiss or Bavarian? Are you any further along the trail?