Interesting story so far
Although I'm not at all sure where the story is going, this is an interesting beginning - the twins insistence on a man being in their room is shocking, even as it is dismissed by their father. I like the fact there are different narrators and that the family picture becomes more complex in the first few chapters. I'd be intrigued to see how the book develops but I'd want more tension and peril than the idea of an imaginary friend.