; or (B) the next of kin of a covered servicemember, or any other individual related by blood or affinity whose close association is the equivalent of a family relationship with the covered servicemember. (6) Grandchild The term grandchild means the son or daughter of an employee’s son or daughter. (7) Grandparent The term grandparent means a parent of a parent of an employee. (8) Isolation or quarantine The term isolation or quarantine , with respect to an individual, means isolation or quarantine because of— (A) a quarantine order under section 361 of the Public Health Service Act ( 42 U.S.C. 264 ); (B) an order or directive of a State, local, or Tribal government; (C) an order of a Federal, State, or Tribal court; (D) a written recommendation of a State, local, or Tribal official that the individual enter isolation or quarantine; or (E) voluntary health monitoring, which occurs when an individual does not have symptoms but is believed to have been exposed to someone who is sick based on guidance issued by the Centers for Disease Control and Prevention or the applicable State, local, or Tribal health department. (9) Nephew; niece The terms nephew and niece , used with respect to an employee, mean a son or daughter of the employee's sibling. (10) Parent-in-law The term parent-in-law means a parent of the spouse or domestic partner of an employee. (11) Sibling The term sibling means any person who is a son or daughter of an employee’s parent (other than the employee). (12) Son-in-law; 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. (13) Uncle