I'm not absolutely sure of this (especially since I've never heard the song), but I know a little Gaelic and a lot of Gaelic songs, and I'd be willing to bet that what sounds like Karrisk yo-na is a girl's name, Cairistiona. It's the Gaelic form of Christina, and gets pronounced variously as Karris tyona, Kahr is chee na, etc. Given the context, it makes sense -- "have girl, will settle down to farming".