Jordan Limas, 18, remains in Weld County jail and is facing criminally negligent homicide charges in his brother's death.
The shooting happened at around 5:30 p.m. Friday in the 4200 block of Grand Teton Road, southwest of Evans in Weld County.
A source close to the investigation told 9NEWS the boy was shot in the chest during a struggle with the brother over a gun.
The boy was transported to North Colorado Medical Center where he later died.
A makeshift memorial was set up near the home.
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