A 5-year-old boy fatally stabbed his tein brother during an argument last week.

The Santa Cruz County Sheriff’s Office said the boys “were fighting, as siblings sometimes do” when one of them “got a small kitchen knife and  stabbed his twin brother.”

“Despite lifesaving efforts by our deputies, emergency personnel, and hospital staff, the 5-year-old passed away at the hospital,” the sheriff’s office said. “In coordination with the District Attorney’s Office and in light of all circumstances discovered by our investigators, no charges will be filed.”

The sheriff’s office did not elaborate other than to say “there is no indication of negligence or criminal activity by any other party,” nor did they comment on how the boy had access to a knife in the kitchen.

“We are heartbroken for the family of these two young children and share in their grief,” the sheriff’s office said. “We will not be releasing any additional identifying information and are asking media to respect the family’s privacy during this difficult time.”

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