I read the first story Arc of Deltora Quest in Montana, but couldn't find the second story arc when coming back to L.A. I was at a library when they said it was going to be the last day they would be open due to the coronavirus outbreak, and stocking up on books, I happened upon another series by Emily Rodda, The Three Doors. I didn't know it was connected to Deltora Quest at first until I found it in the Deltora lineup on Wikipedia, and started to notice some clear refrences in the books.
Three Doors is one of the few series I read straight through with no interuptions from other series like I normally read. I have other books lined up to continue, but this time, I tried it my sister's way.
I predicted the time travel plot-twist half way through book 2 when I was half asleep one night. (Or maybe I figured it out in one of my dreams) It seemed a little wild at first, as my dream didn't really line up with reality, but thinking upon it, it did seem to work.