Jodie - I'm wondering if you have the family in
1891 - it shows Sidney indeed
RG12/1612 68 11
Wilsford, Wiltshire
Village
3 rooms occupiedRobert Stone, head, 48, Agricultural labourer, b. Chirton Wilts
Elizabeth, wife, 47, b. Etchelhampton
Eli, son, 12, Plough Boy, b. Chirton
Arthur, son, 9, scholar, b. do.
Sidney, son, 7, scholar, b. do.

(I suppose you have them in 1881:
http://search.ancestry.co.uk/cgi-bin/sse.dll?db=uki1881&indiv=try&h=23151518 RG11/2041 75 11)
Likely birth: Sidney Stone Jun 1884 Devizes 5a 118