CALDWELL, Idaho — Last month, 18-year-old Onyx Cornish was tragically shot and killed in her Caldwell home. Her mother, Crystal Thompson, is now sharing memories of her daughter with Idaho News 6, reflecting on her vibrant personality and the family's hopes for justice.
Crystal describes Onyx as kind, compassionate, and always putting others first. “She really cared about other people. She would stop anything she was doing if somebody needed her ear to listen,” Thompson said.
Onyx was especially close to her youngest brother, Rain. “They had a really, really close relationship, and this is hard for him,” Thompson shared.
Just two days before her death, the family celebrated Rain’s 7th birthday with a piñata, neighbors, and friends. “It was a really great day… we stayed up till 11 o'clock talking about memories and silly things we used to do. I couldn't have asked for a better last memory,” Thompson recalled.
See what Onyx's mother, Crystal Thompson remembers most about her daughter —
Known for her love of writing, poetry, and unique personal style — including customizing clothing with safety pins — Onyx expressed herself boldly in everything she did.
Her brother, who police say ultimately disarmed their father and called 911 the day of the shooting, is now receiving grief therapy. Thompson praised his strength during the ordeal.
“He's incredibly strong… I can't even believe his levelheadedness through that ordeal. He's amazing, and he's coping very well given the circumstances.”
Court documents show that Delbert Cornish, Onyx’s father, confessed to the shooting and is charged with first-degree murder. Prosecutors are reviewing evidence that could result in additional charges.
Thompson hopes he receives mental health treatment while behind bars. “I just want him to be able to… have the option to receive mental health… that's what I want,” she said.
Cornish is scheduled to return to court on September 17.
Celebration of Life
Onyx Cornish’s celebration of life will be held September 21 at 4 p.m. at Julia Davis Park. Everyone is welcome to attend and honor her memory.
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