"Immediate family" includes the spouse or domestic partner, dependent children, and other dependent relatives, if living in the household. For the purposes of the definition of "intermediary" in RCW
29B.10.320, "immediate family" means an individual's spouse or domestic partner, and child, stepchild, grandchild, parent, stepparent, grandparent, brother, half brother, sister, or half sister of the individual and the spouse or the domestic partner of any such person and a child, stepchild, grandchild, parent, stepparent, grandparent, brother, half brother, sister, or half sister of the individual's spouse or domestic partner and the spouse or the domestic partner of any such person.