The Tennessee bureau of investigation shall maintain a separate fingerprint card file for “Children”, which shall consist of the “children” fingerprint cards submitted to it pursuant to §37-10-206, together with any latent prints believed to be children's prints that have been submitted to it for purposes of identifying missing children. Once each year the bureau shall remove and return to the parent or destroy all fingerprint cards from the children's fingerprint file for children who have become eighteen (18) years of age, unless the child has been reported missing or the child requests in writing that such child's fingerprint remain in the file. Also, the bureau shall destroy any child's fingerprint card upon written request of the parent. The bureau is also authorized to receive “children” fingerprint cards or copies thereof from the federal bureau of investigation when the prints may have been sent directly to the bureau without having also been sent to the Tennessee bureau of investigation as herein provided. The bureau shall not file any of the children's fingerprints authorized herein in any other fingerprint card file. The bureau shall only search the children's fingerprint card file for the purpose of trying to locate or identify children who have been reported as missing children, and the file shall never be searched for the purpose of identifying a child as having committed a crime unless the parent so requests in writing.