Image credit: Courtesy Edward and Terry Fackler

After years of hard work, saving up and an Air Force pension, Terry and Edward Fackler of Everett, Wash., thought they had retirement covered.

Then the student-loan debt started piling up. It wasn't theirs, though, belonging instead to two of their three  children.

Now, with their savings down to $20,000 from $80,000 - and a student-loan debt of $116,000 that they're still responsible for - the couple say they're not so sure that they'll be retiring any time soon.

"Well, I'm still working," church minister Edward Fackler, 73, said.

The Facklers are part of an often-hidden yet sizable number of retirement-age Americans drowning in an estimated $36 billion in student-loan debt for themselves and their children.

"The whole concept that student loan debt is a 20- or 30-something problem is just misplaced," said William Brewer, president of the National Association of Consumer Bankruptcy Attorneys.

The Facklers co-signed for loans to put their kids through college and now their children can't afford the debt payments.

Despite having three college diplomas - a bachelor's and two master's - son Mark Fackler, a veteran, is barely able to pay the $600 monthly, interest only, payments on his loans. He now owes close to a quarter-million dollars.

"I am 40," he said. "They are 73-plus and my mom is a little younger. I don't want to be burden on them. I think about it all the time."

Their mother, 65, is a retired preschool teacher.

Her Social Security checks, in addition to the couple's life savings, now go straight to their daughter's nursing school. They said they were trying to spare Susan, 37, from the kind of loans burdening son Mark, who lives in Texas.

Another son, Brian, 35, is serving in Afghanistan and has no loans.

Financial planners advise parents to co-sign only for loans if they are prepared to pay the debt themselves.

They also say that if a person is considering returning to school for a second career, financial consequences should be considered because student-loan debt cannot be discharged in bankruptcy court.

"It's like a ball and chain that you perhaps drag to your grave," bankruptcy attorney Brewer said.