Edward O'Neal III says his son wouldn't have murdered his best friend, 16-year-old Ryan Robert.
"That's his best friend. He goes over to that house, they come over to my house, they eat. I know his mother, brother, sisters. I don't know what happened," O'Neal said.
Robert, a freshman at Jefferson Davis High School, went missing Friday after he told his mom he would be late coming home from school. His body was discovered Tuesday by Texas Equusearch volunteers near Holmes Road. Investigators say his body showed visible signs of trauma, but the cause of death is unknown.
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Both Robert's mother, Christina Robert, and the mother of O'Neal's son say they believe Robert was killed by his best friend.
"We know who did it. He's confessed to somebody that he did it, and he confessed to more than one person," Christina Robert said.
O'Neal says his son often spoke about the devil and worshiping him, but that doesn't mean he's guilty.
"I don't believe in that. Anybody can say anything," O'Neal said.
O'Neal says his son is currently in the mental health unit of Ben Taub Hospital. The teen's mother says she expects her son will be arrested for Robert' murder. So far, police haven't made any arrests or filed any charges.
As the investigation continues, so does the mourning. Students and staff held a vigil in memory of Robert Wednesday morning on the campus of Jefferson Davis High School. Flags were lowered to half-staff and balloons were released in memory. They say the ninth grader was a good kid and always smiling.
"This is a sad tragedy, this should never happen around here," friend Doris Shaw said. "He was just an all around happy dude. You would never see him with frown or something on his face."