Any part of the intestate estate not passing to the decedent's surviving spouse under section three of this article, or the entire intestate estate if there is no surviving spouse, passes in the following order to the individuals designated below who survive the decedent:
(a) To the decedent's descendants by representation;
(b) If there is no surviving descendant, to the decedent's parents equally if both survive, or to the surviving parent;
(c) If there is no surviving descendant or parent, to the descendants of the decedent's parents or either of them by representation;
(d) If there is no surviving descendant, parent, or descendant of a parent, but the decedent is survived by one or more grandparents or descendants of grandparents, half of the estate passes to the decedent's paternal grandparents equally if both survive, or to the surviving paternal grandparent, or to the descendants of the decedent's paternal grandparents or either of them if both are deceased, the descendants taking by representation; and the other half passes to the decedent's maternal relatives in the same manner; but, if there is no surviving grandparent or descendant of a grandparent on either the paternal or the maternal side, the entire estate passes to the decedent's relatives on the other side in the same manner as the half.