US Department of Labor
The Family Medical Leave Act calls for covered employers to grant an eligible employee up to a total of 12 work weeks of unpaid leave during any 12-month period for one or more of the following reasons:
for the birth and care of the newborn child of the employee;
for placement with the employee of a son or daughter for adoption or foster care;
to care for an immediate family member (spouse, child, or parent) with a serious health condition; or
to take medical leave when the employee is unable to work because of a serious health condition.
For details and necessary forms, visit the FMLA site.