Martin Sheen owes Laurence Fishburne a debt of gratitude — but didn’t realize it until decades after the fact.

In an interview Monday with “Daily Blast Live”, the “Grace and Frankie” star explained how Fishburne saved the life of son Emilio Estevez during filming of “Apocalypse Now” in the Philippines.

As Sheen explained, his son and co-star Fishburne became friendly when Estevez came to visit his dad on the set.

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“We didn’t know about it until about 30 years later. Emilio never mentioned it, but yeah it’s true. I think Emilio was about 12 or 13, and Larry was 14,” Sheen explained.

“They became fast friends and they were out in the boat one day and the boat got stuck, and Emilio got out of the boat to clear the area and he began to sink into the mud and he went under,” Sheen said, “and Larry very quickly moved and pulled him on board.”

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However, both Estevez and Fishburne kept what happened a secret for years, with Sheen not discovering what happened until much later.

“I called Laurence and said, ‘Thank you, I appreciate you saving our son’s life,” Sheen said.