Is that a thing? I say guard-ee as does everyone I've ever heard. The book is The Existential Worries of Mags Munroe and the narrator is Siobhan Waring. I've googled her and she is British but clearly has some Irish connection judging by her first name, and her Irish accent sounds reasonable to me if not exactly the same as any of the few people that I know from rural Galway (who all sound different to each other).
The book is pretty good so far, although the plot hasn't quite kicked off yet. The blurb says that 'something unthinkable happens' and it hasn't so far, but the characters are relatable and the background story building is very good.