The judge of the county court, upon the complaint under oath of any conservator or guardian, may cite any person who has been entrusted by such conservator or guardian with any part of the estate of the ward, any current, suspended, or former conservator or guardian of the ward, or any agent of the ward to appear before such court and may require such person to render under oath a full account of any money, goods, chattels, bonds, accounts, or other papers belonging to such estate which have come into his or her possession, in trust for such ward, conservator, or guardian, and of his or her proceedings thereon. If a person so cited refuses to appear and render such account, the court may proceed against such person as provided in section 30-403.