WASHINGTON—President Obama signed a Defense Department spending bill into law Wednesday that further expands Family and Medical Leave Act coverage for families of employees in the military.

The measure, H.R. 2647, builds on a 2008 law that gave new FMLA rights to military families.

Under the new law, employees will be allowed to take up to 12 weeks of leave when a spouse, child or parent on active military duty is deployed to a foreign country. The 2008 law did not explicitly give FMLA leave rights in that situation.

In addition, the law allows employees to take up to 26 weeks of unpaid leave to take care of a child, spouse, parent or next of kin who was discharged from the military and whose military service aggravated a medical condition that existed prior to the service.

While the new law “makes changes around the edges” of the 2008 law and will affect a small number of employees, those changes will be very important to those individuals, said Matt Morris, a legal consultant with Hewitt Associates Inc. in Lincolnshire, Ill.