I am looking for a book which focuses on a child and his family. I think there was a big house and there were creatures around the house but the creatures weren't visible all the time. There was something that made them visible but I don't remember what it was. The child's family didn't believe him at first.
I didn't read the book but there was a movie I watched that was based on a book series of the same name. It is called The Spiderwick Chronicles (2008). A family movies in to a new house and there are creatures living around it. There's a book that's telling information about them. And the creatures are visible through a stone.
This is the stone from the movie. I don't know if it is the same in the books.