N.J. Stat. § 3B:13-14
If the Federal agency, the sureties on the guardian's bond, any person interested in the benefits in the hands of the guardian or any person as next friend of the ward serves notice upon the guardian that his account has not been filed in accordance with this article, and if the guardian fails to render his account within 30 days from the date of mailing of the notice or from the time of service or within the time as the court may otherwise provide, the court shall remove him. The notice may be mailed to the guardian's last known address.
The cost of the proceedings, as well as the cost incident to an order to show cause when it is necessary to obtain an accounting, shall be paid by the guardian out of his own estate, unless the court shall otherwise order.
N.J.S. § 3B:13-14