Is this the 1871 you were looking for?
RG10/2327 Folio 37 Page 28
West Terrace, Phillack, Cornwall
William Trathen 54 Engine Fitter Phillack
Ann 55 St Erth
/
John ........... lodger 50 Engine Fitter Camborne
// (separate household)
Han....bal Gregory son 17 ........smith Phillack
Ellen dau 15 Domestic Phillack
Charity Thomas mother in law widow 72 Phillack
1861 RG9/1586 Folio 57 Page 14
Hayle, Phillack, Cornwall
William Trathen 45 Engineer Phillack
Ann 45 Erth
Next door are -
Richard Gregory 44 Master Mariner Gwithian
Ann 44 Gwinear
Elizabeth A 19
Emily 18
Richard 16
John 15
George 13
William 11
Hannibal 7
Ellen 5
All children born Phillack. It seems that Charity is Ann Gregory's mum and that the parents Richard and Ann are away from home in 1871, thats my guess anyway, the Gregorys are a separate household and the "son" is relating to the fact that he is the son of the head of the household (Richard) not that he is son of the previous household

IGI also has christening of an Ann Thomas 29/09/1816 Phillack, parents Richard and Charity Thomas
Regards
Catherine
