N.J. Stat. § 54:8A-12
"Related to taxpayer" means related by blood, to the extent of any lineal descendant or ancestor of taxpayer, other children or grandchildren of a parent of taxpayer, children of a grandparent of taxpayer, and grandchildren of a grandparent of taxpayer who are receiving institutional care for physical or mental disability and who had been members of taxpayer's household prior to institutionalization; or related by marriage, to the extent of a stepchild, stepparent, stepbrother or stepsister of taxpayer, the parents, brother or sister of the spouse of the taxpayer, or the spouse of a child of taxpayer; or related by household, to the extent of a person having taxpayer's home as his principal place of abode and being a member of taxpayer's household for the taxable year. Brothers and sisters of the half blood shall be regarded as though of the whole blood.
N.J.S. § 54:8A-12