The implications for FMLA are that the employee is entitled to leave under the Family and Medical Leave Act if the child develops a serious health condition—provided, of course, that the employee meets the organization’s other criteria for FMLA eligibility. In releasing the letter, Department of Labor officials spoke of the many family compositions and in loco parentis—or standing in for a parent—relationships that characterize society in the United States. A parent’s partner may be of the same sex, a grandparent can step in to raise a child, the occasional child goes to live with a neighbor—the possibilities are varied.

Said Labor Secretary Hilda Solis, “No one who loves and nurtures a child day-in and day-out should be unable to care for that child when he or she falls ill.” And it can work the other way around. Labor spokespeople noted that an adult child who was raised, at least partly, by a nontraditional parent is entitled to leave to care for that person “if [he or she] becomes ill, frail, or elderly.”

Looks like there are added wrinkles. Observers have discerned two notable changes that seem to be embedded in these new rules. First, FMLA regulations that were effective in mid-January 2009 defined in loco parentis as someone “with day-to-day responsibilities to care for and financially support a child.” However, the interpretation letter says that a stand-in parent need do only one of those two—either care for or financially support a child, but not necessarily both.

Second, FMLA regulations dictate that a husband and wife who work for the same employer make take a total of only 12 weeks of leave to care for or bond with the same child. But it seems that that limitation will not apply to other kinds of parents, such as a biological parent and a grandparent, or a same-sex couple, who both work for the same employer. The new regulations seem to say that both such people could take 12 weeks’ (or more under some state laws) leave to care for the same child. That could potentially present employers with problems, if a traditional parenting couple learns that two untraditional parents have access to more leave from the same employer. One way employers could avoid these complications is to create a policy limiting leave to 12 weeks for any two employees caring for the same child.

Can just anyone claim the status of in loco parentis to a child? That, too, will depend on an employer’s policies and practices. Employers who wish to decide can use the factors courts have used, such as the age of the child, how much the child depends on the employee, the amount of support provided, and the extent to which the employee performs duties commonly associated with parenthood.