Lots of Scots-Irish Kennedys in the US. There’s a Kenedy Co. in Texas (pop. about 400)—I don’t know who it’s named for but probably a Scots-Irish Protestant rather than an Irish Catholic Kennedy.
The name Kennedy is very common in SW Scotland—Ayrshire, probably also in the areas just to the south. That’s where a lot of the Scots settlers of Northern Ireland came from.