I just had a look at the index at ScotlandsPeople (free), and both 1828 entries are there. "Found one entry" for each (marriage and bapt) after I marked BANFF under parishes, date from [1 Jan] 1828 to [31 Dec] 1828, with their surname and forename(s). On the marriage I wrote Spouse's Name as "ann cheyne".

Unfortunately my credits have expired so I couldn't "View" - which they make you do for 1 credit in case you have a list of possibilities to choose from. Then they charge you more credits to see the scan.

I would look at the marriage, and also at John's bapt - we already know they have included his birth date in the record, and it would be interesting to see whether they say he was born elsewhere. If it says Isle of Man do let us know.

Sue