Hello Tiffaney,
I cannot find a marriage of a Cuthbert Nairn, and Margaret Highet, anywhere on the Scottish, records.
There is however two possible births to couples with those names.
Jean Nairn, born 14/April/1782. Stewarton, Ayr.
Parents, Cuthbert Nairn, and Margaret Highet.
Marrion Nairn, born 06/March/1774. Stewarton, Ayr.
Parents, Cuthbert Nairn, and Margaret Highgate.
This is most likely the same couple.
Alas your date of birth for Cuthbert Nairn, is 1794.
Are you sure your birth year for your Cuthbert, is correct, and how did you arrive at his birth date.
By 1851. the oldest Cuthbert Nairn, in Ayrshire, is 48 years old, and married to a Elizabeth, and living in Mauchline, Ayr.
Regards,
Jonn.