N.J. Stat. Ann. § 3B:5-5.1

1. If it appears to a fiduciary administering an intestate estate that there may be individuals whose names or addresses are unknown who may be entitled to participate in the distribution of the estate, the fiduciary shall make a diligent inquiry, under the circumstances, to identify and locate the individuals. The actions taken by a fiduciary shall be those that have some reasonable likelihood of finding the individuals and are reasonable in cost compared with the amount of the distribution involved.