(1)    The county department or, in a county having a population of 750,000 or more, the department or an agency under contract with the department shall investigate the personal and family history and environment of any child transferred to its legal custody or placed under its supervision under s. 48.345 and of every expectant mother of an unborn child placed under its supervision under s. 48.347 and make any physical or mental examinations of the child or expectant mother considered necessary to determine the type of care necessary for the child or expectant mother. The county department, department or agency shall screen a child or expectant mother who is examined under this subsection to determine whether the child or expectant mother is in need of special treatment or care because of alcohol or other drug abuse, mental illness or severe emotional disturbance. The county department, department or agency shall keep a complete record of the information received from the court, the date of reception, all available data on the personal and family history of the child or expectant mother, the results of all tests and examinations given the child or expectant mother and a complete history of all placements of the child while in the legal custody or under the supervision of the county department, department or agency or of the expectant mother while under the supervision of the county department, department or agency.

   (2)   At the department’s request, the county department shall report to the department regarding children who are in the legal custody or under the supervision of the county department and expectant mothers of unborn children who are under the supervision of the county department.