Brain Snacks: Tasty Tidbits of Knowledge
The Internet invented an unverifiable legend for the fairy swear word "D'Arvit." (Source.)
Eoin is pronounced Owen. Good to know, isn't it? (Source.)
Much of the magic in this book is steeped in Irish folklore and mythology. The Encyclopedia of Celtic Mythology and Folklore has tons of great background information on this tradition, as well as entries for all sorts of fairies who show up in this book. (Source.)
The magical parts of Ireland in the book are actually considered magical or sacred in the real world. (Source.)