Imagine living your entire life unaware that you had a sibling, and then imagine finding out you do, and that it's someone you've actually met before.

Ron Cole and Duncan Cumming each held on to black-and-white photographs taken when they were childhood friends, when they didn't know they were family. (CBC) That's what happened to 71-year-old Ron Cole and 72-year-old Duncan Cumming, who reunited in Ottawa on Thursday after decades apart.

Cumming and Cole were adopted in Ottawa as babies. Coincidentally, they grew up just five blocks away from each other in the city's Glebe neighbourhood and went to the same elementary schools.

What's even more surprising is that they were childhood friends, and each has held on to a black-and-white photo of themselves as children.

Cumming contacted Children's Aid, learned of siblings

Cole, left, and Cumming, right, visited a school they attended in Ottawa's Glebe neighbourhood about 60 years ago. (CBC) Much later in life, Cumming contacted the Children's Aid Society for information about his birth mother, and found out he had siblings. He had been searching for Cole for nearly 20 years when they were reunited by phone last year.

A volunteer group called Parent Finders Ottawa helped reunite the adopted siblings. Monica Byrne, who works for the group, spent years putting the pieces together.

"When I phoned Duncan and I said, 'You have a brother, Ron Cole.' He said, 'Not Ronny Cole!'," Byrne recalled. "When I called Ron he said, 'Oh my gosh, we were kids together. I have a photo of him here in my hands.' ... It had fallen out of his bookcase two days before. He said it was just a complete out-of-the-blue thing."

"Today is the reality. I never thought it would happen," Cole said after arriving at the Ottawa airport on Thursday with his wife, Ronna Drozda-Cole.

The Coles live in Saskatchewan, and Cole said he didn't know he had a brother until he got the call last year.

"I almost hung up on them," Cole said. "They phoned me in the evening and I thought, 'Oh yeah, this was a scam.' "

Cumming lives in Guernsey, an island in the English Channel.

To watch CBC Ottawa reporter Ashley Burke's full TV story on the brothers and their reunion, click here.