I'm also researching the McDonald line. Some years ago I was sent a chart showing my lineage. Only now - having begun again to browse through my notes after a long pause - have I noted that the wife of Angus Ban McDonald (b. 1744) is listed as being a Mary McIntosh, and showing that the couple had a daughter, Janet McDonald (who married a John Kennedy).
However, Angus Ban McDonald was in fact married to Elinor (Ellen) McDonnell. They sailed from Scotland together in 1786 with their many children, and settled in the Glengarry area.
I'm hoping that someone has details regarding Janet McDonald's lineage.
I've tried hard to find a connection between Angus Ban McDonald and a Mary McIntosh (who may have been the daughter of John of Donald Ban McIntosh), but without success.
Any insight greatly appreciated. (-: