A 6-year-old girl died in Kentucky over the weekend after being shot by her 4-year-old brother.

According to WSMV, the siblings were at their grandparents’ home in Hopkinsville on Sunday evening while their grandfather was cleaning his .38 caliber handgun. The grandfather told reporters that he thought the gun was unloaded when he stepped away for a moment.

The grandfather said he believed that the 4-year-old boy picked up the pistol and shot his sister in the mouth, causing a bullet to lodge in her spine.

The girl was taken off life support after being taken to Vanderbilt Children’s hospital later that evening.

“He was going to clean the gun, set the gun down, left the area for just a second and heard the shot,” Hopkinsville Police Chief Guy Howietold WTVF.

“People have to be careful,” he added. “If they’re going to have a weapon they have to be responsible, and it’s unfortunate that it takes tragedy for people to come to the realization they have to be responsible.”

It was not immediately clear if charges would be filed against the grandfather.

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