Son or daughter
Son or daughter means -
(1) A biological, adopted, step, or foster son or daughter of the employee;
(2) A person who is a legal ward or was a legal ward of the employee when that individual was a minor or required a legal guardian;
(3) A person for whom the employee stands in loco parentis or stood in loco parentis when that individual was a minor or required someone to stand in loco parentis; or
(4) A son or daughter, as described in paragraphs (1) through (3) of this definition, of an employee's spouse or domestic partner.