; daughter-in-law The terms son-in-law and daughter-in-law , used with respect to an employee, mean any person who is a spouse or domestic partner of a son or daughter, as the case may be, of the employee. (28) Uncle; Aunt The terms uncle and aunt , used with respect to an employee, mean the son or daughter, as the case may be, of the employee's grandparent (other than the employee's parent). . (2) Inclusion of adult children and children of a domestic partner Section 101(12) of such Act ( 29 U.S.C. 2611(12) ) is amended— (A) by inserting a child of an individual’s domestic partner, after a legal ward, ; and (B) by striking who is— and all that follows and inserting and includes an adult child. . (b) Leave Requirement Section 102 of the Family and Medical Leave Act of 1993 ( 29 U.S.C. 2612 ) is amended— (1) in subsection (a)— (A) in paragraph (1)— (i) in subparagraph (C), by striking spouse, or a son, daughter, or parent, of the employee, if such spouse, son, daughter, or parent and inserting spouse or domestic partner, or a son or daughter, son-in-law or daughter-in-law, parent, parent-in-law, grandparent, grandchild, sibling, uncle or aunt, or nephew or niece of the employee, or any other individual whose close association is the equivalent of a family relationship with the employee, if such spouse, domestic partner, son or daughter, son-in-law or daughter-in-law, parent, parent-in-law, grandparent, grandchild, sibling, uncle or aunt, or nephew or niece, or such other individual ; and (ii) in subparagraph (E), by striking spouse, or a son, daughter, or parent of the employee and inserting spouse or domestic partner, or a son or daughter, son-in-law or daughter-in-law, parent, parent-in-law, grandchild, sibling, uncle or aunt, or nephew or niece of the employee, or any other individual whose close association is the equivalent of a family relationship with the employee