***Posted Again, with date mistakes corrected :-P *****
Thanks Graham for your message.
Since my original post I have identified the following information about the Thomas Mordey b.1824, a Shipwright: -
Birth - 15 Feb. 1824, Sunderland (ref IGI)
Address 1841 Census - Pembottom Street, Bishop Wearmouth, Sunderland, County Durham (surname transcribed as "MORDER")
Address 1849 Marriage Cert - 14 Hedworth Street, Sunderland, County Durham. He married ELIZABETH DIXON b. 1827, Sunderland. They had 4 children - Hannah, William, Thomas (my GG-GrFthr) and Elizabeth Jane Ann.
Address 1851 Census - 7 Back Lion Street, Bishopwearmouth, Sunderland, County Durham
Address 1861 Census - SEARCHED, BUT COULD NOT FIND
I am not sure when, where and how he died. One possibility is that he died at sea but i have not been able to confirm or find any information to the contrary.
As for a link with a Mary DOWNS I'm sorry to say there does not appear to be one with this Thomas MORDEY. However the Thomas MORDEY that Mary DOWNS did marry may be connected in some way, possibly cousins related via 1?, 2? 3? or more generations back?.