(a) A minor and the minor’s parent, guardian or custodian may agree to an arrangement for alternative voluntary residential placement, in compliance with the “Child Care Act of 1969”, without court order. Such placement may continue as long as there is agreement.
     (b) If the minor and the minor’s parent, guardian or custodian cannot agree to an arrangement for alternative voluntary residential placement in the first instance, or cannot agree to the continuation of such placement, and the minor refuses to return home, the minor or the minor’s parent, guardian or custodian, or a person properly acting at the minor’s request, may file with the court a petition alleging that the minor requires authoritative intervention as described in Section 3-3.