What book has a magic forest behind a grandmother's house?

Question

I remember once I read a book in the library, and now I want to re-read it. I don't know the name though, however, it was such an entertaining read I can remember the story.

• 2 Children (1 boy 1 girl), mum and dad were going to take them somewhere as a surprise but logs fall on their car and kill their parents

• Then they go to their grandmother's house with a weird forest behind it that they shouldn't go in.

• They go in anyway

Now I can only remember some events that happened during the story after that point.

• The boy gets turned into a rabbit and cyclops were going to turn him into a casserole. The cyclops were sharing one eye between all 3 of them.

• Towards the end of the book the girl gets turned into a bird and the boy gets turned into a mouse and then the strange magic guy was going to kill the mouse by shutting a book on it.

I can't really remember anything else.

Answer 1

This is "Shadow Forest" (Also published as "Samuel Blink and the Forbidden Forest").

Samuel Blink is the hero of this story, but he doesn’t know it yet. Right now, he and his sister Martha are in the back of his parents car. He has no idea a giant log is about to fall from the sky and change his life forever. He doesn’t know that he and Martha will be forced to move to Norway and eat their Aunt Eda’s smelly brown cheese. He hasn’t the slightest clue Martha will disappear into Shadow Forest. A forest full of one-eyed trolls, the sinister huldre-folk, deadly Truth Pixies and a witch who steals shadows. A forest ruled by the evil Changemaker. A forest so dangerous that people who enter never return.