Hi Rhodie,
I have not found the marriage of William and Sarah, did find these Birth/Christenings. Do you already have the census entries?
John Hammet Born 18 December 1788 Christened 21 December 1788 Tolpuddle
Parents William Hammett and Mary
FHL Film 1239251
James Hammet Born 7 April 1801 Christened 21 June 1801 Tollpuddle
Parents William Hammet and Carolinah
FHL Film 1239251
James Hammett Christened 23 August 1851 Tolpuddle
Parents James Hammett and Harriet
FHL Film 1239251
Frances