CHICAGO (CBS) — A dozen couples, who are celebrating their 50th wedding anniversaries this year, renewed their vows Saturday at the Field Museum, and talked about what makes a marriage last.

Gary and Donna Marino, of Burr Ridge, said they met at a Northern Illinois University social event.

“I was a senior and she was a freshman and we had a sorority-fraternity turnabout day, and I met her there,” he said. “I thought she was the prettiest thing I’ve ever seen — and she still is.”

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It took while for Donna to figure out Gary was the one.

“I didn’t think anything (at first),” she said. “Then he started pursuing me and we started going out.”

When they married on Dec. 1, 1962, she said, people didn’t believe in “starter marriages.” But they agreed that passion is an ongoing must to keep a marriage alive.

Tony and Mary Drobnik, of Schaumburg, said there was chemistry immediately. She made pizzas for his roommates, who played bridge together. One night, they brought him along.

“I thought he was just so wonderful,” she said.

Tony said he knew right away that they’d “be best friends for at least 50 years.”

They say remaining best friends is the best way to make love last.

It was not love at first sight for Ralph and Marilyn Klein, who met at a church square dance.

“I don’t remember all the details,” she said. “Things happened at a later date.”

It also took Ralph a while.

“Actually, I asked one of her friends out first,” he said. “But eventually I got around to the real prize.”

Ralph said similar values help keep a marriage together.

“Forgiveness comes in, and I’m sorry,” he said. “There’s the old joke that says we’ve only had one argument and it’s still going on.”

Marilyn puts it differently.

“It’s better than, ‘I love you,’” she said. “My favorite line is, ‘I love being us, with you.’”

Asked if she felt good for another 20 years together, she said, “I was thinking 50.”

Several of the couples walked away with presents, courtesy of the Field Museum, where they renewed their wedding vows in a brief, three-minute service.

One couple received a free stay at the Essex Inn, and another at LaQuinta Inns. Another couple received an annual Sky High Pass to the John Hancock Observatory, while another received a pair of tickets to “Catch Me If You Can,” courtesy of Broadway in Chicago.