CALDWELL, Idaho (Scripps News Boise) — After disarming his father inside their Caldwell home, 15-year-old Lucian Cornish says he ran for his life down the street — moments after learning his sister, Onyx, had been murdered on Aug. 18.
In an exclusive interview with Scripps New Boise, Lucian detailed what happened that day and how he remembers his sister.
“I remember when I was running away, I thought to myself, ‘Am I dreaming?’ Like, my brain was just going in different directions. This has to be fake,” Lucian said.
(L) Onyx Cornish, (R) Lucian Cornish (Scripps News Boise)
What started as a normal afternoon quickly turned into a nightmare when Lucian got home from school. That’s when his father, Delbert Cornish, allegedly told him he had shot and killed his sister.
“He started bawling, crying, not like a normal sad cry, like scream crying, and I was like, ‘OK, what’s going on?’ And then he said, ‘I killed your sister.’ Like, what? And then he reached into his pillow on the couch and pulled out a gun,” Lucian recalled.
Lucian says his father then tried to force him toward his sister’s room, even firing a shot into the floor to get him to listen.
“I just kept trying to get him to let me leave,” said Lucian. “After a while, he said, ‘Turn around and walk behind you.’ I didn’t want to face my back toward him, so I just walked backward. I said, ‘Dad, I’m your son. Why are you doing this?’ And I think that touched him.”
MORE | ‘I did it, dude’: Court docs show Idaho man confessed to killing daughter
Fearing for his life, Lucian says he lunged at his father, grabbed the gun and pinned him against the wall.
He said his actions terrified him.
“Then he stood up and pointed the gun at me like this. I knew that it’s either I’m gonna have to fight or I’m just going to die,” he said.
Delbert Cornish appears in court via video conference. (Scripps News Boise)
Before Lucian escaped, he says his father made one final statement.
“He said, ‘This is your last time seeing me, I’ll be dead 30 seconds after you leave.’ I already kind of figured that. So I said, ‘I know, Dad. I love you,'” Lucian remembered.
After a tense struggle, Lucian managed to run two blocks before calling 911.
Now, he says he’s trying to process what happened—and leaning on his family for support.
“I know that I’m not OK. But I will be OK,” Lucian said. The Cornish family is still working to heal, and a GoFundMe remains active to help with expenses.
Delbert Cornish is expected back in court on October 13.
This story was initially reported by a journalist and has been, in part, converted to this platform with the assistance of AI. Our editorial team verifies all reporting on all platforms for fairness and accuracy.
