Two Hawaii men who have been best friends for decades got a special gift over the holidays when they found out through DNA testing that they were related to each other.
As it happens, Robi737 is none other than Macfarlane's best buddy since the sixth grade, Alan Robinson, a former 737 pilot for Aloha Airlines.
They bonded in the first place over being unsure of where they came from, KTRK reported, because Macfarlane didn't know his father and Robinson, who had been adopted, didn't know either of his biological parents.
So when Macfarlane, with the help of his family, made a decision to research his lineage, they uncovered a truly unexpected surprise.
'So then we started digging into all the matches he started getting, ' Macfarlane's daughter Cindy Macfarlane-Flores explained. "I thought I'll never know my birth mother, I'll never have any nieces or nephews".
He added that Mr Macfarlane, who is 15 months older, had been like a big brother to him all along.
Mr Robinson told KHON2: 'I had a younger brother that I lost when he was 19, so I never had nieces or nephews.
"He's the tackle, I'm the end, and we never knew, you know?"
Here's where Robinson comes in.
It turned out Robinson used the same website to find answers about his family.
"It was a shock", Macfarlane said.
Turns out Robinson and Macfarlane share identical X chromosomes, indicating they had they same birth mother.
'Yea hairy arms, that did it!' Macfarlane shouted.
The two announced their discovery at a party for friends and family on Saturday, Dec. 23.
'It was an overwhelming experience, it's still overwhelming.
"You know we'd go to Punaluu to go skin-diving, I'd be making noise in the water splashing around, he'd be teaching me how to do it right", he told KITV.
"This is the best Christmas present I could ever imagine having", Mr Robinson said.
Awwww! The bros say they plan to travel and enjoy retirement together.