There is a theory that Mary Mcleod (Smith)'s mother was named Henrietta McSwane and not Mary MacAulay.
I realize this is not a primary source:
https://www.thoughtco.com/ancestry-of-donald-trump-1421916
"Mary Smith was born on July 11, 1867, in Tong, Scotland, to Donald Smith and Henrietta McSwane. Her father died when she was just a little over a year old, and she and her three siblings were raised by their mother. Mary died December 27, 1963."
I'm looking into this!
Dear private
From the link which you provided we find the entry for Mary Smith MacLeod's parents:
"14. Donald Smith was born January 1, 1835, to Duncan Smith and Henrietta MacSwane, the second of their nine children. He was a woolen weaver and cottar (peasant farmer). Donald died on October 26, 1868, off the coast Broadbay, Scotland, when a squall of wind overturned his boat.
15. Mary Macauley was born about 1841 in Barvas, Scotland.
Donald Smith and Mary Macauley were married on December 16, 1858, in Garrabost on the Isle of Lewis, Scotland. They had the following children:"
We see in the link that you provided that Henrietta McSwane is listed as the mother of Mary MacLeod (Smith) as you mentioned above, but then further down in the page the mother is Mary MacAulay. I expect that it was just the result of confusion when the article was written. Henrietta McSwane is the grandmother of Mary Smith MacLeod (the mother of her father).
Here is the birth record for Mary Smith MacLeod found on Ancestry.com:
Name: Mary Smith
Gender: Female
Birth Date: 11 Jul 1867
Birth Place: Stornoway,Ross and Cromarty,Scotland
Father: Donald Smith
Mother: Mary Macaulay
FHL Film Number: 6035516