The child in a strict religious household has to hide their worship of a pagan god, all while the various “gifts” from their patron become harder to explain.
btw it's fantasy, you really don't need to worry about your world map making "sense" geologically or whatever. make that river flow backwards from the sea into the mountain.
One of my favorite tricks for designing alien species/cultures is to take a real animal with an interesting lifecycle and think about what that biology would translate to if they had human intelligence