Yes, I knew about Donald, actually his military record states he died of bronchitis while in hospital.
I knew about Reginald as well.
I found a 1911 census which shows a Grace H Dawson (could be Mrs. George H)as head of the house, occupation- housekeeping, Edwell (could be Edna Ethel) occupation-nurse, Regenald (Reginald)occupation-something to do with wood and Donald occupation-bookkeeper.No mention of George.
I believe Rachel Jane left George on their farm in 1910 and took these three children with her. Her son Roy was already in Vancouver by this time along with his wife Kate Beebe Macdonald and their two daughters Edith Lea and Helen Lois. This is the Kate B. in Duart Cemetery, Rachel Jane's daughter-in-law.
I am thinking she returned to the farm at the time of George's death. Roy and family also returned to Ontario
in 1920. This is pure specualtion on my part but I am going to try to find something around 1920 in Ontario.