Benjamin "B.J." Eastman’s son, Ben, disappeared in the middle of the night on June 23, 2018. Eastman says at first, he thought his son was at his good friend Benny Marquez’s house, but after the 16-year-old didn’t come home for three days, Eastman says he grew concerned.

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Eastman says that he logged on to Ben’s Facebook account to see if there were any clues to his whereabouts. He tells Dr. Phil in an exclusive interview airing Wednesday that he saw references to an argument between Ben and Marquez about a girl.

“Ben had said, ‘Well, we talked about this already. You were drunk.’ And then Benny responds, ‘Oh yeah, I was just drunk. I forgot. It’s all good.’ That was the end of it,” Eastman says. “I wish I’d had known about that argument.”

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Ben’s body was later discovered in a shallow grave on property owned by Marquez’s relatives. Marquez and his brother, Jonathon Adamson, have been charged with first-degree murder, rape, tampering with evidence and unlawful disposal of remains. Both have pleaded not guilty to the charges.

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How Benjamin Eastman Learned His 16-Year-Old Son Had Been Murdered