(a) On receipt of the petition, the court shall set a hearing.
(b) A copy of the petition and notice of the hearing shall be delivered to the parent, conservator, or guardian of the child by personal service or by certified mail, return receipt requested, at the last known address of the parent, conservator, or guardian.
(c) Proof of service under Subsection (b) must be filed with the court at least three days before the date of the hearing.