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I found the following for Robert and Elvira, There is more information on family search. Need to know if this is the right family and I will continue looking
I found this Robert and Elvira on Familysearch.org it is a free site but you need to register to search.
You did not mention any possible dates or residences. This death certificate for Robert is from the state of Washington, USA
Newspaper Obituary for Robert and several family members listed
Find a Grave with photo of Robert Ferguson.
Dear Mr. Miller,
Thank you for posting your request on History Hub!
For an overview on how to begin your research, we suggest that you review the FamilySearch Research wiki for Belize Genealogy, as well as Belize Colonial Records. In addition, the document titled Suggestions and Advice for Family History Researchers may be of use.
We hope this is helpful. Best of luck with your family research!