This is the first time I've done this so hope I do it correctly. I've just read this bit
The parents of Alexander (1796) were John McPherson and Margaret Young who married at Huntly, Aberdeenshire on 7 Oct 1788. John's parents may have been William McPherson and Jean Wilson, with a son John having been born at Cairnie, by Huntly on 29 Mar 1763.
and have to tell you that I'm sorry but John's parents weren't William McPherson and Jean Wilson. Their John married Anne Wilson and never left Cairnie, Aberdeenshire. If anyone wants any information on the Cairnie McPhersons I've quite a tree.