Camilla,
I just saw your post on the Phinn family topic. Below is what I have on William before the war:
"William Charles Middleton Grant was born at 28 Warrender Park Terrace, Edinburgh on 26th February, 1888, the eldest son of William Grant and Margaret Ruthven Thomson. When he was 7 his mother died, having been ill for a year; and, for the next four years, the children where brought up by a succession of housekeepers until his father remarried Janet Macmillan Ferrier, a Sunday School teacher, in 1899. They were both devout and active Christadelphians and William would have been brought up in a home full of bible reading, self examination and prayer. With his father's religious writings and public speaking, as well as publishing "Glad Tidings" every month, his childhood was likely to have revolved around the Christadelphian church and his father's passion for Zionism. In 1901 he was a 13 year old scholar at the Royal High School, Edinburgh. He was vaccinated. As an adult he was 5ft 8 1/2in tall, with a 32 inch chest, fair hair and blueish grey eyes.
On leaving school he became a bank clerk. There is no record of him working for RBS so it is possible that his father used his contacts to get him a job with another local bank or that he worked at St Andrew's Sq with his father. RBS have no surviving records for Head Office for this period. On the 4th May,1909, at the age of 21, he arrived in Quebec on the "Cassandra" and settled in Canada, possibly with help from his uncle James Miller Grant who had emigrated some 20 years earlier; although, if he saw him, he did not stay in Toronto for long. By the 1911 Census, only 2 years after emigrating, he was in Winnipeg, Manitoba, was married to Hulda Camilla Unger and had a one year old daughter, named Margaret after his mother. His mother-in-law Hulda Unger was living with them. He described his religion as Presbyterian and his nationality as Canadian so he obviously had no intention of returning to Edinburgh. His occupation was accountant. It is not known whether he followed his parents into the Christadelphian church."
I hope that helps with your research,
Jenny