To such summons a copy of the petition must be attached and copies of the summons and petition served on the personal representative (if not the petitioner), the heirs at law of the decedent (if the decedent died intestate or the time to challenge a will admitted to probate has not expired), the devisees under the decedent’s will (if any), any person who has properly presented a claim against the estate which remains unresolved, any interested person effected by the proceeding, and any other interested person as required by the court in its discretion, in like manner as summonses and complaints are served in civil actions in the circuit courts. If there are minors the court shall appoint guardians ad litem who must be served with copies of the summons and petition and the appointment, and who must acknowledge acceptance of their appointment as guardians ad litem to the probate court prior to being served with the summons and petition. Nothing herein precludes the parties interested in the proceeding from accepting service of the summons and petition and consenting to the sale as prayed for in the petition.