Except as provided in subsection (b) of this section, a person shall be licensed by the Department as a child care home before the person may exercise care, custody, or control over a child who is alleged to be or is adjudicated delinquent or in need of supervision. This section does not apply to: a parent of the child; an individual related to the child by blood or marriage within 4 degrees of consanguinity under the civil law rule; a guardian of the child; a person who exercises temporary custody or control over the child at the request of a parent or guardian of the child and who is not required otherwise to be licensed; a person who has the care, custody, or control of the child through placement by a parent or grandparent of the child in contemplation of adoption, if the requirements of § 5–507(b)(2) and (c) of the Family Law Article are met; an institution that has a child care institution license under this subtitle or § 5–509 of the Family Law Article; an institution operated by a unit of the State or a political subdivision; or a foster care provider with whom the child is placed by: a licensed child placement agency; a local department of social services; the Secretary of Health; the Department; or a court of competent jurisdiction.