According to the Tetsworth PRs, Martha Payne was baptised on 31 Aug 1806, daughter of James & Elizabeth.
Siblings were:
Thomas July 7 1799
Martha Feb 25 1802
Hannah Nov 18 1809
Robert 25 Mar 1812
John Nov 5 1815 (father James is described as a labourer)
Mary Oct 12 1817 " "
Richard July 11 1819 " "
Strangely, I can't find a burial for the first Martha.
The parents' marriage was also in Tetsworth:
James Pain & Elizabeth Cross July 30 1798.
He signed, she made her mark.
Witnesses were William Butler & William Hatton (not sure about the surname of the second witness but he witnessed a few marriages on the same page, so probably a 'professional'.)
Hope this helps.
Jill