That, too, can be solved with a Canadian setting, where the Irish immigration was largely pre-Famine and the Scottish immigration continued much later than in the U.S.
That’s always the fate of the biggest guy on the block, as the US would learn in the 20th/21st century when it was the BSD.
The Scots certainly wouldn’t have moved to an Irish settlement out of any great love for the Irish. Nor would the Irish have felt any kind of fellowship for Scotsmen.
But, to use the original Maryland colony as an example… Maryland was founded as a haven for Catholics. Most Protestant Englishmen despised Catholics, and wouldn’t have LIKED the idea of living in a Catholic colony. But if there was desirable land and good economic opportunities available, well, Protestant would hold their noses and move to Maryland. And Catholics would welcome them, reluctantly, because they needed the human and financial capital the Protestants would bring. (As it turned out, Protestants soon outnumbered Catholics in Maryland, and quickly made the Church of England the official colonial religion.)
In the same way, Scotsmen WOULD have joined Irish settlers in a new venture, IF they believed there was some prime real estate available, and plenty of opportunity to get rich.
And the Irish would have welcomed the Scots, despite some misgivings, IF they believed the Scots could provided skills or funds they needed to make the new settlement viable.
Rightly or wrongly at that time Americans and emigrant groups tended to divide Irish immigrants into "Lace curtain"or Scots Irish,who were considered respectable and “Shanty Irish” those who mostly left Ireland because of the Potato famine.
Shanty Irish were stereotyped as brawling drunks often involved in petty crime so it could well be the case that other migrants would not be overly enthusiastic about co locating themselves with them if given the opportunity not to.
I don’t think “lace curtain” is synonymous with Scots-Irish at all Lust4life. I believe it more refers to class divisions within the mainly Catholic migrants and their descendents post-1845.
Yes, my Great-Grandparents were referred to as “lace-curtain” Irish by some of their fellow churchgoers.
Re: the OP, would the creatures have to have come along with people at all? Plants, foodstuffs, fabric, and even cattle would have been imported as well. I could certainly see a Cluricean (is there a Scots version?) following a shipment of whiskey into a ships hold.
For a Beansidhe (blue hag in Scotland I think?) you’d need the head of the family to move - a rarer circumstance.
A Cobblenee (sp?) would follow any bright metal. . . You’d need to move a live tree for a dryad to go . . .
A bodach or a Kelpie might follow an ill-fated ship, I 'd think. the bodach might have to ride inside.
I’m just building on childhood stories here, the “official” definitions of these things may differ.
Well…I’m not sure how much how they could have gotten here matters, given that the creatures (even in the frame of the story) only exist in the imagination of a ten-year-old boy who is trying to cope with a family secret; I doubt Ready cares too much about how the creatures in Mister Fisher’s book came with the immigrants. But now that you mention it, it might make sense to have him have a few explainations when he’s insisting to his parents that they’re real.