Gallant

As Schwab is one of my favourite writers and ghosts one of my favourite subjects, it's no surprise that I really enjoyed this.
I agree with other reviewers that it's more of a very young adult or older childhood book rather than an adult read but that didn't make it any less enjoyable. I didn't agree with the fact that a lot of reviewers found Olivia really annoying. She's much more relatable and less obnoxious than Cassidy from Schwab's Cassidy Blake series, which is actually written for children. I found her mutism made her more interesting because she had to find more inventive ways to express herself or communicate, though these can be naughty as she's still a pre-teen and probably not as mentally/emotionally developed as normal having been raised by a religious orphanage. While she is communicating with the reader because it's from her POV, I didn't find her thoughts whiney or insufferable.
However, the plot didn't really feel as planned out as it should have been and, if you're an avid reader of the author like myself, you'll see a repeat of some ideas from their earlier books. It's obvious Schwab likes to write about ghosts and she has a specific idea of what they would look like, which is a theme throughout their descriptions in different books.
This reminded me a lot of Coraline, with some obvious influence from both Crimson Peak and The Haunting [on Hill House]. If you like fantastical or gothic horror, definitely give this a try.