SOLVED Boy and girl from Canada go to Wales/Ireland, somehow end up in ancient/mythological times [s]

[Gallimaufry]

Boy and girl, siblings in their teens from Toronto, are sent to live with aunt and uncle or maybe friends of their parents. Their father is a judge. They're being sent away because the dad didn't approve of the girl's boyfriend.

They get to Wales or Ireland, not sure which, and befriend a strange farmhand named Peadar. They follow him through some trees one day and end up in an ancient land where all the mythological people and creatures exist, and have to find a way to stay alive.
And I think Peadar is some kind of important warrior.

The only other thing I remember is that the boy can't cook, and claims it's women's work - and the farmhand points out that he makes himself completely dependant on a woman by not learning how to do it himself.

I think the girl ends up falling in love, but they have to go back to their own world and the relationship can't work.

I'm not sure when it was published, I read it a couple years ago but it wasn't a new book. Might have been 1970s/80s but just guessing.

[K.V.]

Sounds like this is O.R. Melling's The Druid's Tune. The Druid's Tune It's been reissued several times with different covers.

[Gallimaufry]

That's the one! Thank you so much! :)