Matthew McConaughey has revealed the one word his mum said to him that made him realise Woody Harrelson could be his brother.

The two actors, who both come from Texas, are two of the most recognisable names and faces in Hollywood and are great friends.

The pair first met in 1999 when they both starred in comedy film EDtv. They went on to star opposite each other in one of the biggest shows of 2014, ‘True Detective’.

However, it appears the friends could actually be related.

The pair had a conversation while they were on holiday in Greece with family, including with McConaughey’s mother, Mary Kathleen ‘Kay’ McConaughey.

He explained what happened in an interview with ‘Let’s Talk Off Camera with Kelly Ripa’: “In Greece a few years ago, we’re sitting around talking about how close we are and our families.

“And my mom is there, and she says, ‘Woody, I knew your dad’. Everyone was aware of the ellipses that my mom left after ‘knew’. It was a loaded K-N-E-W.”

He said: “And that’s part of our bromance, right? My kids call him Uncle Woody. His kids call me Uncle Matthew etc etc. And you see pictures of us and my family thinks a lot of pictures of him are me. His family thinks a lot of pictures of me are him.”

McConaughey said the pair went on to unpack what this ‘knew’ could mean and did some maths.

Harrelson’s dad, Charles had been on furlough at the same time McConaughey’s mum and dad were in their second divorce (they married three times).

Charles was a convicted contract killer and armed robber, convicted of two murders and acquitted of another.

Harrelson said: “The year of [McConaughey’s] birth, nine months before, she was on a sabbatical from her relationship with his supposed father, Jim.”

McConaughey added: “Then there’s possible receipts and places out in West Texas where there might have been a gathering, or a meeting, or a ‘knew’ moment.”

Maury Povich has reached out to the pair, offering to help them with a DNA test which the pair have contemplated.

McConaughey responded to Povich’s offer saying: “I don’t know if we’re gonna do it on your show, but I like the way you’re thinking.”

However, so far they have shied away from this option as McConaughey is said to be ‘uneasy’ at the idea that his father might not be his biological dad.