We need hard facts around the early 1900s to connect a Mary Baillie to the births of a Jessie and James Baillie around that time.
I am always hard about verification in all research

otherwise it is all speculation. We all know how we can lose a life on spec....
The big hard fact we have, Myra, is the birth address for your grandfather James and his sister Jessie, 15 Rumford Street Bridgeton.
I love the fact that your Mum is adding info with what details you and your sister are finding.
From what we have talked about...Father John Baillie and mother Ann Morrison, census details that I can see from 1881 to 1901 (marriage here to view on SP
https://familysearch.org/ark:/61903/1:1:XTBP-M6N to help you work back to John and Ann's parents)...feel we now have found the main key piece of data to firm up at this time. Ann Morrison/Baillie's death in 1920 in Bridgeton. Her son John was the informant to her death. Her address for her death looks to be the key (thank you Annie

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