"A boy must rescue his sister after she finds - and wants to stay - in an almost-world beneath her bed, where their mother is still alive"--

It seems like Mom's death meant losing everything else Charlie Price loved, too. And just when he thinks things can't get any worse, his sister, Imogen, starts missing school and making up lies about their mother. But everything changes when one day he follows her down a secret passageway in the middle of her bedroom and sees for himself: Imogen has found a parallel world where Mom is alive! There's hot cocoa and Scrabble and scavenger hunts again and everything is perfect... at first. As Imogen starts to spend more and more time on the other side, Charlie knows he has to uncover the truth, before he loses himself, the true memory of their mother, and Imogen... forever.