Cheryl MacLennan informs me that Stewart had a brother A. Gordon MacLennan (b.1889, Sidney, Nova Scotia) who was a prominent Presbyterian minister and Doctor of Divinity at Shadyside and Bethany Presbyterian churches in Pennsylvania.  His wife was Leanna MacLennan, who was born in Ohio. They had no children. Stewart P. and A. Gordon were the two most prominent Presbyterian ministers in the country at that time.  And they had another brother, John, who was a railroad engineer in Canada.

Andrew Roberstson gives Donald's lifespan as 1852-1940 (I think he made a typo and meant 1920, the date I know is right from the probate of his will).

Canadian Census. Duncan is listed in the 1881 Canadian Census as a 28-year old living with his mother, his father has died. The name is spelled MacLellan. His occupation is listed as Engineer. He was born in Nova Scotia. He is listed in 1891 living in Sydney, Cape Breton, Nova Scotia. He says he was born in Nova Scotia and that his mother and father were born in Scotland. He is age 39 and his occupation is Locomotive Engineer. His family includes wife Annie and sons Stewart, Kenneth and Gordon.

Duncan is also listed in the 1901 Census still living in Sydney. He says he was born in Nova Scotia and that his mother and father were born in Scotland. He is age 39 and his occupation is Engineer. His religion is Presbyterian. His family includes wife Annie and sons Stewart, Kenneth and Gordon and daughters Margaret, Rebecca and Jessie. The Census asked each person for an exact birthdate and an age. Duncan's birthdate is given as 15 Jul 1853 or 1855 and his age as 48. Since the Census was taken in May '01, to be 48, his birthdate would have to have been 15 Jul 1852. One other interesting point is that his native tongue is stated to be Scottish Gaelic while it is English for the rest of his family.

Turning to the 1911 Census, Duncan now lives in South Bay, Cape Breton. His birthdate is given as Jul 1852 and he is 58 -- so my best guess for Duncan's birth date is 15 Jul 1852. I'm unable to read his occupation in this Census, I'm not sure it is engineer though. He lives with wife Annie and Kenneth, Margaret, Rebecca and the girl named Jessie in 1901 whose name I cannot read in 1911.

On a compiled list of marriages from old Cape Breton newspapers, I found the citation of the marriage of Annie MacLennan of Sydney to D. MacLellan of Sydney at Sydney 29 Dec 1881. Since the date fits so well with what is known about Duncan and Annie (they weren't married yet when Census was taken earlier that year but were certainly married before 1884 when Stewart was born), I believe this is indeed Duncan and Annie. And note, it is the second reference I have found where Duncan's last name is spelled MacLellan.

Duncan wrote his will 20 Jul 1918, it was probated 14 Oct 1920. It was a simple will whereby he left everything to Annie and she was appointed Executrix. Duncan signed his name "McLennan".

Andrew Roberstson gives Annie's lifespan as 1852-1921.

Canadian Census. Anne is listed in the 1881 Canadian Census as a 23-year old living with her parents in Sydney. She was born in Nova Scotia. She is listed in 1891 still living in Sydney, now with her husband and three sons. She is 35 years old.

Things are pretty much the same in 1901 though three daughters have jkoined the family. The Census asked each person for an exact birthdate and an age. Anne's birthdate is given as 19 Jan 1856 and her age as 45. Her native tongue is English.

Turning to the 1911 Census, Anne and Duncan now live in South Bay. Her birthdate is given as Dec 1856 and she is 54.