Gail, do you have the family tree linking you to Sir John or to one of his siblings? I too had the same type of story, however, in my 15 years of research trying to connect my family to his, I discovered we are related to John Sandfield MacDonald, first Premier of Ontario. Stories got switched over the years.
With that being said, I still do research on Sir John and have lots of notes of his family. Would be glad to share anything I got.
Paul MacDonald
Hays, Kansas