This is an update of my own research so far:
As well as Charles Smith Murison in 1899, Maggie also had two more illegitimate children, James Murison in 1900 and Mary Murison in 1905, all born at Bogend on the Estate of Shiels, Midmar, Aberdeenshire.
In 1907, Maggie married John (Hay) Scott, whose parents Adam Scott and Elizabeth Milne lived at Mains of Newhall, Cookney.
On the 1911 census, John and Maggie are living at Knocklom in Cluny parish with their daughter Flora Scott aged 3. The census shows 2 children of the marriage with 1 living. I have not located a birth record for Flora.
In 1912, John and Maggie had a daughter Elizabeth Murison Scott while living at Dalherick Cottage, Midmar.
I have been in touch with a granddaughter of James Murison, and through that I know James married Annie Christie in 1928, and they had 5 children: Anne, Robert, James, Malcolm and Graham.
I was told John and Maggie's 2 daughters were Elizabeth and Annie, but I think the Annie may be incorrect. The birth record I found for an Annie Scott in that area in the same time period had different parents.
I am keen to learn more about the other siblings lives, particularly Mary but also Flora and Elizabeth, and would be happy to hear from any family members.