In the spring of 1964, Charlie Di Pietro took a gamble on love.

He was at a dance at the Cresthaven Country Club in Queens with a friend when they spotted the most beautiful girl in the room. Charlie's friend, Sal, bet him $5 that he would not be able to dance with her.

When she refused, Charlie didn't back down. In fact, he offered her $2.50.

"Mary, what a great idea! We can go dancing every week now," Mary's friend told her.

She agreed to the dance, and the rest is history. Charlie and Mary Di Pietro were married in 1966.

Over the years, they bought a house in Massapequa, raised two sons and welcomed five grandsons into their family. But an ongoing issue kept arising in their relationship. He never gave her the $2.50.

"She always brings up the $2.50. And I say to her, 'one of these days.'"

That day came recently during their 50th anniversary celebration. Charlie paid Mary the $2.50 plus interest. In the end, the dance cost him $220.

They also renewed their wedding vows.

"She's still beautiful. I could go another 50 years with her," says Charlie.