Wow, you've really got it down pat. I guess we are talking too many years difference. Some McLeans may have been left in Ireland, and they were sailors here and could go back and forth, but no records or letters found...not that they don't exist. But it was 1735 on, not 1830 or so.
Just thought it would be a nice coincidence me living here.
The more I read about this NH Londonderry the more special it becomes.
For example...
I think Johnny Appleseed spent summers here apprenticed to an apple farmer named Mack. His uncle settled here and his mother died when he was fifteen or so, and his father was in the war assigned to George Washington's unit for the duration. Johnny and his sister needed looking after and they could have been sent here to their uncle. He had to learn about Apple farming somewhere, and there were three apple orchards here, harvested and sent up and down the east coast.
Never did love history as much as I do now. :)
Thanks, and good luck with your hunting.
Judy