Anne,
Following is a list of potentially relevant Dewar Births in Eastern Ontario which I got from Michael Stephenson's website, ontariogenealogy.com. Numbers 3,9, 13, 18 are the ones in my family line that I am particularly interested in but the record for "More" (14) could also be of interest given the apparent interchangeability of the names More, Nancy and Ann, but Roderick and Ann had a daughter named Ann (1837) so it seems unlikely they were in the same family.

I have a digital copy of the record for Donald but none of the others. I am trying to pin this family to a particular piece of land. The confusion (on my part at least) seems to be, which township, Lochiel or West Hawkesbury (Caledonia?) and which lot, 24 or 29. The record I have for Donald looks like Lot 29 but it could be 24. The concession seems to 7 for either possibility. Do you have location information for Ann (3), Donald (9), Mary (13) and William (18)? 

 
1. DEWAN MURDOCH    .. ANGUS - MARY .. 1822
2. DEWAR ALEXANDER    .. DUNCAN - JANET .. 1827
3. DEWAR ANN    .. RODERICK - ANN .. 1837
4. DEWAR CATHERINE    .. DONALD - JANET .. 1837
5. DEWAR CHRISTY    .. DUNCAN - JANET .. 1825
6. DEWAR DONALD    .. DONALD - ISABELLA .. 1841
7. DEWAR DONALD    .. DUNCAN - JANET .. 1821
8. DEWAR DONALD    .. HUGH - CHRISTINA .. 1836
9. DEWAR DONALD    .. RODERICK - ANN .. 1829
10. DEWAR MALCOLM    .. DONALD - JANET .. 1839
11. DEWAR MARY    .. ANGUS - FLORA .. 1836
12. DEWAR MARY    .. ANGUS - FLORA .. 1839
13. DEWAR MARY    .. RODERICK - ANN .. 1836
14. DEWAR MORE    .. RODERICK - NANCY .. 1826
15. DEWAR RODERICK    .. DUNCAN - JANET .. 1823
16. DEWAR SALLY    .. ANGUS - FLORA .. 1837
17. DEWAR WILLIAM    .. DONALD - ISABELLA .. 1837
18. DEWAR WILLIAM    .. RODERICK - ANN .. 1840

Barry