Haw. Rev. Stat. § 346-238: Service.

(a) Service of the notice shall be made by delivery of a copy thereof together with a certified copy of the petition to each person or entity to be given notice either by personal service, by certified mail, return receipt requested and addressed to the last known address, by publication, or by other means authorized by the court. Upon a showing of good cause, the court may waive notice to any party except the vulnerable adult.

(b) Service shall be effected at least forty-eight hours prior to the time fixed in the notice for hearing when held pursuant to section 346-232(a), or at least fifteen days prior to the time fixed in the notice for an adjudicatory, disposition, or review hearing, unless the party otherwise was ordered by the court to appear at those hearings.