I've just come across your message regarding the above people.My mother was a Kerr and I've been trying to track down all the family that went out to Alberta Canada.
Mary(Bannon)Hunter b=1881 was married to Hugh Kerr b=1870 Lanarkshire,Scotland d=1926 Tannochside,Lanarkshire,Scotland.There where seven children of that marriage one you have missed George Hunter Kerrb=1912,the Margaret Hunter Kerr b=1915 you have as Margaret Stevenson Kerr---is this right??
As you say when Mary's husband died she came out to Canada where the rest of the family had settled.I managed to find out that Margaret Hunter Kerr marriade a Reginald Dockstader in Alberta but have had great difficulty in getting access to records from that area to find out any more.My dear aunt Mary Kerr(age 91) 1st cousin once removed of Mary Hunter Kerr had contact info many years ago after they imigrated,but had lost touch over the years and has wanted me to try and find out what become of them all.
If this information is of use and you care to part any details---as I can hopefully do likewise,I would look forward to filling in any gaps on both sides.