(a) As used in this Code section, the term "court appointed special advocate" means a volunteer who has been screened and trained regarding deprivation, child development, and juvenile court procedures and has been appointed as a guardian ad litem by the court in a deprivation case.

(b) The court at any stage of a proceeding under this article, on application of a party or on its own motion, shall appoint a guardian ad litem for a child who is a party to the proceeding if the child has no parent, guardian, or custodian appearing on the child's behalf or if the interests of the parent, guardian, or custodian appearing on the child's behalf conflict with the child's interests or in any other case in which the interests of the child require a guardian. A party to the proceeding or the employee or representative of a party to the proceeding shall not be appointed. In deprivation cases, an attorney or court appointed special advocate, or both, may be appointed as the child's guardian ad litem.