American cop Tom Decker used his detective skills to locate his great-great-grandmother’s house using nothing but one old photograph from the 1920s.

He first believed the house was located in either Dublin or Cork, but his hunt brought him to Beechfield Street in the Ballymacarret area of east Belfast, in March 2014.

On his first trip outside the U.S., the Michigan policeman traveled to Ireland to see the house and met with its current owner, Dan Mallon.

"This has been so much bigger and more exciting than I ever thought possible," said Tom. "My family back home has been following my progress and they are as overwhelmed as I am."

The 41-year-old Mallon, who was born and bred in the house, said, "It's really been lovely to have been able to help Tom to find out more about his family roots."

The Belfast Telegraph reported that the two men were put together by the "Mooney" program on RTE Radio 1, which picked up on the story.

When starting out on his search to locate the family home, Decker only had a faded black and white photograph taken in the 1920s during his ancestor Rose Ann Decker’s (nee Carson) trip to visit Irish relatives. The house in the photo turned out not to be of Rose’s family home but that of her sister Maggie McGouran.

While Decker was flying to Dublin, a friend of his posted the photo on the Reddit website with a promise of a $150 reward to anyone who could help identify the house.

"I will Paypal you $150 USD if you can find this building in Dublin on Google maps (original image of house).” read the ad, which was posted on February 19.

"My friend landed in Dublin today and is there for 10 days."

By the time Decker reached Dublin, more than 200 people had responded. reports that searches in various Census records and directories of Dublin addresses showed nothing promising, but crucial clues were posted to Reddit by posters Scamallnaoi and ptegen of a Michigan marriage record for Rose Carson to Horace Decker. This showed Rose’s parents as Charles Carson and Mary Mullen.

A passport application form for Rose Decker also gave a likely timeframe for Rose’s trip of July 1920, and also a date of birth for her on the 31st October 1864 (possibly estimated) and an important clue in the form of the place of birth shown on the form – Sanfield.

Further searching located a passenger manifest confirming that Rose had traveled back across the Atlantic at age 54 after her trip in October 1920 on the “Empress of France.” Traveling on the same ship was a Margaret Mullen.

Church marriage records confirmed the link to a likely location in Ireland. Rose’s parents were married in Saintfield, Co. Down, very similar to the reported place of birth of “Sanfield” appearing on the passport application.

Census records showed a probable match for the family, with both parents and the two youngest children living at a townland named Ballygowan, Co. Down, and not too far from Saintfield.

A passenger arrival record showed a Rose Decker, as well as Margaret Mullen, arriving in Liverpool on August 18, 1920 on the “Empress of France.” Both women gave their European address as “51 Beachfield, Belfast.”

A search of the address on Google maps, made it clear they had found the right house.

Potential 'cousins,' brother and sister Joe and Briege McGouran, were also there to meet Decker. They believe that they are connected through Rose Ann's sister Maggie, who married Joseph McGouran.

*Originally published in 2014

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