Hi Foz
Firstly, regarding Sarah Cairns' parents Samuel and Isabella Brown. A word of caution, even with the names of their parents from their death certs., you are going to have the issue of researching in Ireland where records are much more difficult to source. If you have viewed Samuel and Isabella Brown's death certs. and they contain their parents' names, you might want to try a new post on the Ireland Board here on RootsChat.
In respect of Thomas, did you get the father's name as being John from his DC? I think there may have been some misreporting on his DC of his father's name which I think is likely to be James not John. Remember we have a likely birth entry for Thomas, an actual extract:
THOMAS MCEWEN Christening: 12 MAY 1822 Old Luce, Wigtown, Scotland
Parents: Father: JAMES MCEWEN Mother: ANN LATIMORE
I've just looked on IGI, and there is also a marriage banns entry for this couple, also an actual extract:
ANE LATIMORE
Parents: Father: PAUL LATIMORE
Marriages: Spouse: JAMES MCEWEN
Marriage: 28 MAY 1821 Old Luce, Wigtown, Scotland
Children showing to this couple on IGI:
1. THOMAS MCEWEN Christening: 12 MAY 1822 Old Luce, Wigtown, Scotland
2. HELEN MCEWEN Christening: 14 NOV 1824 Old Luce, Wigtown, Scotland
3. ANN MCEWEN Christening: 02 MAR 1828 Old Luce, Wigtown, Scotland
4. MATILDA MCEWEN Christening: 20 JUN 1830 Old Luce, Wigtown, Scotland
5. JESSIE MCEWEN Christening: 09 OCT 1831 Old Luce, Wigtown, Scotland
6. ELIZABETH MCEWEN Christening: 27 NOV 1836 Old Luce, Wigtown, Scotland
7. JANE MCEWEN Christening: 22 APR 1839 Old Luce, Wigtown, Scotland
I'll have a look in the censuses for father James to check out his occupation.
Regards.
Monica