The Book of Lost Things by John Connolly

The Book of Lost Things centers around twelve-year-old David, who is grieving the death of his mother and struggling with his new stepmother and her children. As World War II rages on, David finds solace in reading and a mysterious book that seems to speak directly to him. When the book’s stories start to merge with his reality, David is drawn into a dark and magical world where he must face his fears and confront mythical creatures to find his way back home and save his loved ones.