Thank you to all who made valuable contributions to my search for info on this family. Yes, it would seem that Samuel Boyd Gordon was neither 40 as his gravestone suggests on his death in 1964, or 42 as the press report. I have found his birth recorded to Nancy and James Gordon 7 May 1919. I know from past experience that a year or two in either direction seemed to suffice for birthdays back in the day. He seems to have been their fourth child, not fifth. I had already traced James and Nancy back to him being the son of Wm James of Kirkfields who married Ellen Booth of Kirkhills in 1885, and his father was James. I also was considering a line from Hugh and Selina Boyd Gordon, because of the Boyd addition to the name but this now is irrelevant, though this line is to my DNA match. My Great Grandfather John Gordon born 1864 appears to have had an Uncle James born 1834 who married late per my DNA match on Ancestry, they were from near the Dark Hedges, so I conclude that I am most likely related to Gordons of the coal yard through him. It was the Telegraph death announcement that provided the info that put it all into place, and this was a paper I never would have delved into for local affairs, usually looking up old Chronicles and Constitutions. I had not wanted to go into the area involving Samuel Boyd Gordon's children's deaths as the person who contacted me seeking the family link shared fairly sensitive info on the sad conditions that prevailed for these young people. Thank you all who contributed - some useful info on GRONI may help others too.
