Investigators say they've made no arrests and there are no suspects and won't say what they think may have led to the stabbing.
"He had decided he was going to turn his life around and was to be baptized this Sunday, as a matter of fact," Doug Lockhart said of his only son. Now instead of seeing him baptized, this father will bury his son, still unsure of the circumstances that led to his death.
The elder Lockhart said the months leading up to his son's death were not easy ones. "He saw her the day she disappeared. He was the last one to actually see her. She got in the car with some other man," Doug Lockhart said.
Her disappearance has prompted a state police investigation where investigators, at one point, questioned Lockhart.
"He was beside himself when Marina came missing. And he spent hours and hours and hours searching for her. He would go and follow up on ideas that he had of where she might have been," explained DJ's father.
That's what Doug Lockhart said his son was doing Thursday just hours before he died, checking on a lead he thought he had about Boulter's disappearance.
"He was trying to figure out what happened to the mother of his child," said Doug Lockhart.
"He loved that girl and he loved that baby and he was working on being a good father," said Doug Lockhart.