Do these 8 Indiana siblings hold the secret to wedded bliss?

KNOX COUNTY, Indiana -- We came to Indiana looking for one of life's most elusive secrets.

We'd heard that deep within Knox County, Indiana -- back among cornfields -- there was a cluster of people who had all unlocked the mystery of a long and happy marriage.

But here's what's even more remarkable: they're all related.

Together, the eight Clinkenbeard siblings have amassed nearly half a millennia of marriage -- 449 years in total. So I figured if anyone had the secret to wedded bliss, it would have to be these couples.

I gathered them for a series of interviews, and here's what I learned: If you want to stay married forever, women, you need to speak your minds.

"I could tell when she was ticked," said Jim Clinkenbeard.

Or not.

"I usually keep my mouth shut," said Barbara Kirk.

And men, you need to be deferential.

"You treat a lady like a lady," said Bruce Clinkenbeard.

Or not.

"I said, 'I love to fish and I'm not going to change that,'" said Paul Clinkenbeard.

Unfortunately, almost everything I got was a contradiction.

Really, the only thing the Clinkenbeards could agree on was what their mother Dorothy taught them and told them repeatedly -- that, except in very rare circumstances, divorce should not be an option.

"She instilled that in us kids, you know," Bruce said.

"My mom was pretty stickler about that," said Bill Clinkenbeard.

"When we said 'I do,' to me that meant however long we lived," said Dan Yagle.

It meant suffering through some bumpy times, but the oldest brother John says it's well worth it in the end.

"We've been married 65 years," he said.

John sat on the couch alone because his wife, Lillian, is in the hospital.

"I don't know how I'd get along without her."

I never got my easy answer to what makes a happy marriage.

"We love one another," Paul said.

But I did get eight solid reasons -- to never give up looking.

As Ed Kirk put it, "I couldn't imagine life without her."

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