Details of all 12 million children under the age of 18 in England will be recorded soon on a database called the Children's Index. Parents have yet to grasp that professional opinions on, say, their abilities as a parent, or concerns about their children's development and health could be entered by teachers, GPs and social workers — without their knowledge or consent. Nor that the Children's Index will be linked to other databases dealing with such controversial issues as a young child's potential to become a delinquent.