Matthew McConaughey has shared details of his parents’ volatile relationship ― and how it came to an end.

The Oscar winner revealed in his new memoir Greenlights that his father, James McConaughey, died while having sex with his mother, Kay. It was just how his dad predicted, the actor recalled.

“I got a call from my Mom. ‘Your dad died.’ My knees buckled,” Matthew wrote in an excerpt shared by People.

“I couldn’t believe it. He was my dad. Nobody or nothing could kill him. Except mom. He’d always told me and my brothers, ‘Boys, when I go, I’m gonna be makin’ love to your mother.’ And that’s what happened. He had a heart attack when he climaxed.”

The Beach Bum actor, who was born after his parents married each other for the third time, characterised their bond as “the Pacific Ocean in a storm”.

“They were, at times, violent,” he told People. “As I say in the book, that is how they communicated.”

His father died in 1992. His mother is now 88.