« Reply #13 on: Wednesday 22 May 13 09:51 BST (UK) »
If you don't already have a copy, Thomas' marriage certificate to Elizabeth Hall would confirm his father's name and occupation and would probably be more reliable than a death certificate where the information would be from a third party, even if that was a child. As Lizzie has said, they're not always accurate.
Yes I know Death Certs aren't always accurate, but sometimes they are! And all information stated is correct. Tring comes not only from the Death Cert its stated on the 1851 census also.
That's as maybe, but his baptism does NOT appear in the Tring PRs so it is quite possible that the family moved into Tring at some point before migrating into London. There are Allens in there, but not a Thomas at the right time nor parents James and Elizabeth baptising children. There are other James Allen marriages but not to an Elizabeth. Just because Thomas listed Tring on the 1851 Census, doesn't mean he was born/baptised there just that's the place he believed he was born. The younger brother of one of my ancestors, both born in Ivinghoe, lists his birthplace on several census as Berkhamstead.

FindMyPast don't have all the parish registers for Hertfordshire online at the moment so they could have been in a surrounding parish but they could also have quite easily have been over the border in Buckinghamshire. It might be worth you getting a search done from Bucks FHS to eliminate that option if you are certain that you have the correct parents -
http://www.bucksfhs.org.uk/index.php?option=com_content&task=blogcategory&id=17&Itemid=199.
You say all the information is correct on the death certificate, do you have Thomas on the 1841 Census with his parents and/or his marriage certificate to confirm father's name and occupation?
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