<human>: I have searched *everywhere* for this book, and haven't been able to find it. I google the storyline a hundred times and nothing ever comes up. We had to read this book for this thing called Battle of the Books in like 5th grade. I was supposed to be the one to read it, and I only read the first few pages, but now I want to find it again to actually read it. So here's basically how the story goes, from what I remember:

A young girl lives in a village where there's a tale that some kind of monster lives up in the mountains. I think her uncle ventured up to the mountains and never came back when she was a kid. So eventually as she gets a little older curiosity gets the best of her and one day she decides to travel up there to see what's really up in the mountains, and what became of her uncle. I think she might have taken her pet cat with her. 

Please Reddit! You're all I have left!

Give me the gist of the text in a nutshell
<bot>: I'm looking for a book about a girl who ventures into the mountains to find out the truth about a tale saying a monster lives up there, and tries to find what became of her uncle who did the same.