N.J. Stat. § 3B:12-32
If the person for whom a testamentary guardian has been appointed under the will of a parent, spouse or domestic partner as defined in section 3 of P.L. 2003, c. 246(C.26:8A-3)has not been adjudicated as an incapacitated person in accordance with N.J.S. 3B:12-24 and the Rules Governing the Courts of New Jersey, the person named as the testamentary guardian may apply to the court in the manner provided in N.J.S. 3B:12-30 for a judgment designating that person as the temporary guardian of the person or of the estate, or of both the person and estate of the alleged incapacitated person until the issue of incapacity has been determined. Upon the determination of the issue of incapacity, the court shall either enter a judgment confirming the appointment of the testamentary guardian or vacating the appointment of the temporary guardian.
N.J.S. § 3B:12-32