Hi Palaja
Just some thoughts. The two marriage entries in Perth and Essex would refer to the marriage banns being read in each place. Most probably Alexander and Elizabeth were already living in Copford where the actual marriage took place. The marriage banns in Perth would probably refer to Elizabeth if this is where she was from.
In your position I would follow up on:
1. 1841 Census index for a possible family for Alexander. You know the name of his father and that he was a farmer. Have you got access to Ancestry's index for 1841 Scotland. Unfortunately, Stirling has not yet been transcribed by FreeCen (or Perth for that matter). Apart from Ancestry, your only other option would be Scotlands People, which is pay to view. With some luck, you might find Alexander still at home with his family in 1841.
2. The other avenue to follow up is to check whether Alexander and Elizabeth followed Scottish naming patterns. It might confirm Alexander's father's name and give you clues re his mother's name. This might also help with Elizabeth's family, unless you have details of these already. Also, check whether they used any surnames as middle names for their children, can also be a hugh clue.
3. It might be that Alexander's birth/christening details are not to be found. As you know, some OPRs have not survived or maybe his birth wasn't registered. But at least with some indication of the mother's name, you might be able to find some siblings' details recorded on IGI.
4. I don't know how consistent he was with his age on the censuses. It might be worthwhile doing a +/- 3 years on a possible birth year of 1821.
Regards.
Monica
