It was heartbreaking: a brother and sister, torn from their parents and brought into foster care. Kit, eighteen months old, had a broken arm and his sister Molly, three, was withdrawn and scared. The parents said they weren't to blame and appeared to dote on their children. Could the social services have got it wrong? If so, who caused Kit's injuries and why were the children ill so often? The truth, when it finally came out, was unbelievable and far more shocking than I could have ever imagined.