« Reply #8 on: Tuesday 27 August 13 12:03 BST (UK) »
well, more records have come online since you last posted, but I can't see a death reg or burial for Thomas.
FreeReg has transcriptions of parish records up to 1837 for St Elli and there's a baptism for John Oldham, son of Thomas & Mary, bp 16/5/1830.
http://www.freereg.org.uk/The family were in Llanedi in 1841 and the burial records for that parish haven't been transcribed as yet.
Mary's remarriage ref is
Mary Oldham june qtr 1841 Llanelly vol 26 pg 892 with John Bowen on the same page
I've checked the death regs for Llanelly district from sept qtr 1837 to 1841 and I
think this could be Thomas's death reg
Thomas Older june qtr 1838 Llanelly vol 26 pg 439
It's the only occurrence of that surname in the district between 1837 & 1974 and the GRO index can contain errors because of using copies of copies of quarterly returns.
Cornwall: Allen, Bevan, Bosisto, Carnpezzack, Donithorn, Huddy, James, Retallack, Russell, Vincent, Yeoman
Cards: Thomas (Llanbadarn Fawr)
Glam: Bowler, Cram, Galloway, James, Thomas, Watkins
Lincs: Coupland, Cram
Mon: Cram, Gwyn, John, Philpot, Smart, Watkins
Pembs: Edwards (St. Dogmael's)
Yorks: Airey, Bowler, Elliott, Hare, Hewitt, Kellett, Kemp, Stephenson, Tebb