With more children in care in England than ever before, and the government about to publish a report on the deaths of two toddlers at the hands of their parent's new partners, Panorama investigates how social workers make critical decisions about children's lives. Granted rare, exclusive permission from the family courts, reporter Louise Tickle hears from families who have been damaged by decisions made by one local authority. With the government pushing social workers to step in earlier than ever, what happens if they go too far, too fast?