Of course, I couldn't read about Mollie Hunter and not read some of her actual books! I began with The Kelpie's Pearls. The protagonist is an old woman of magic living in a world that increasingly doesn't understand the old ways. Devious and dangerous Kelpies have a rich history here in Scotland, so this was a good story to serve as introduction.
Reading all of this has given me some great ideas to chew on for my PhD - thoughts of liminal characters, magic, and Scottish folklore. Also, this idea of animism and the attraction of young readers to fantasy, when they are going through the transition from childhood to young adult, holding tight to wonder, while embracing the more mature/rational adult existence. All very interesting!
At any rate, if you're not familiar with Mollie Hunter, and you'd like to enjoy some good mid-grade steeped in Scottish lore, I highly recommend you read some of her books!