"She's the one that started this whole thing!" the actor said
“What does K-Mac have to say about this?” the host asked, to which McConaughey responded: “She's the one that started this whole thing!”
“We're all sitting around in Greece one night talking and my mom out of nowhere in a little pause goes, ‘Oh, I knew your dad, Woody...,’ ” the actor said.
He continued, “And we all went, ‘What was the ellipsis about? And what was the knew about?’ And she goes, ‘Just saying, we might have frequented the same similar place out in West Texas one time when he was on furlough.' ”
“And we all went, ‘What? What, are you going to leave it there?’ ” he continued. “Now we gotta go do some DNA tests.”
McConaughey first brought up his and Harrelson's potential connection on Let's Talk off Camera with Kelly Ripa in April while teasing their aptly-named project Brother from Another Mother.
"Where I start and where he ends and where he starts and I end has always been a murky line, and that's part of our bromance, right?" he told host Kelly Ripa at the time. "My kids call him Uncle Woody, his kids call me Uncle Matthew."
McConaughey continued, "My family thinks a lot of pictures of him are me, his family thinks a lot of pictures of me are him," before sharing the story of the Greece revelation with Ripa, 52.
According to McConaughey, the timeline also appears to match up — it’s possible his mom “knew” Harrelson's dad during a time when she was separated from husband James Donald McConaughey.
While the two may take a DNA test sometime in the future, the Dallas Buyers Club actor told Ripa it would be “a little harder” for him than Harrelson.
"It's a little easier for Wood to say, ‘Come on, let's do it,' because what's the skin in it for him?" he said. "It's a little harder for me because he's asking me to take the chance to go, ‘Wait a minute, you're telling me my dad may not be my dad of 53 years,' and believe in it?”
"I got a little more skin in the game,” he added.
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Shortly after McConaughey’s chat with Ripa, Harrelson discussed their potential brotherhood on The Late Show with Stephen Colbert — and echoed his longtime pal’s hesitation about taking a DNA test.
"The thing is, we want to go for a test, but for him, it's a much more big deal," he said of McConaughey. "I mean, he feels like he is losing a father. But I'm like, ‘No, you're gaining a different father and a brother.’ "
McConaughey and Harrelson first teamed up for the 1999 satire film EDtv. They have since reunited onscreen for the 2008 comedy film Surfer, Dude and in the first season of HBO's True Detective.
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