ST. LOUIS (AP) — Two young cousins were livestreaming from a St. Louis apartment when one child fatally shot the other before killing herself in what family members say was a tragic accident.

Police are still investigating Friday’s incident in which a 12-year-old girl, Paris Harvey, shot a 14-year-old boy, Kuaron Harvey, before shooting herself. Police initially described it as a murder-suicide.

The girl’s grandmother, Susan Dyson, told the St. Louis Post-Dispatch that she saw the Instagram Live video the two cousins were making together at a downtown St. Louis apartment the family had rented to celebrate March birthdays.

“It wasn’t a situation where they were arguing or anything like that,” said Dyson, who is from the Dallas area. “They were playing with the gun, when they shouldn’t have been. Of course, they shouldn’t have been doing it. I think it just went off. It went off by mistake.”

Family members said the cousins had been raised close together. Kuaron’s mother and Paris’ father are siblings.

Paris and Kuaron were alone in a bathroom making a video in the mirror before the shooting happened. Family members said that after Kuaron was shot, the video showed Paris reaching for the gun and it may have accidentally gone off again. They said they believed the gun was Kuaron’s. Both children were shot in the head.

“It was no murder. It wasn’t a suicide,” said Shinise Harvey, 35, Paris’ mother. “It was a freak accident. It happened.”

Harvey said she had not seen the video but family members had described it to her. She said the cousins were “trying to be too hip.”

Paris and Kuaron Harvey were often together making videos and pulling pranks. Family members said Paris, who was one of nine children, was a funny seventh grader who loved getting her hair and nails done and had a beautiful voice. They described Kuaron as a goofy eighth grader who had long been able to do back flips.

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