Hi Jem, I found an MI for Susan Robertson and her husband.
Erected by Donald Dow and Susan Robertson, his wife, Criag of Stenton, in loving memory of their sons Donald, Pte. 4/5 Black Watch, died of wounds received in action 20th February 1919 aged 36 years, Thomas died in Edinburgh 21st June 1920 aged 36, and are both interred here, Alexander died in Ballinluig 8th March 1923 aged 35 years, the above Donald Dow died 30th Sept. 1929 aged 79 years and his wife Susan Robertson died 28th May 1931 aged 82 years, Annie Dingwall wife of the above Thomas Dow died 8th march 1968 aged 87 years.
Cheers Evelina