File on 4 investigates claims that parents whose children suffer from a crippling illness that leaves them sick and permanently exhausted have been falsely accused of child abuse. Parents of children with Myalgic Encephalomyelitis (ME) reveal how they have been investigated and referred for child protection measures on suspicion of a rare form of child abuse known as Fabricated or Induced Illness (FII). FII, also sometimes known as Munchausen's Syndrome by Proxy, is extremely rare and occurs when a parent or carer exaggerates or deliberately causes the symptoms of a child's illness. One charity says FII is being used inappropriately by education and health professionals. We talk to families who claim the stress caused by this accusation has made their children worse. With doctors divided over the best way to treat children, what's the impact on families? Reporter: Matthew Hill Producer: Nicola Dowling.