Investigators said the 18-year-old who pulled the trigger is the victim's friend.
The Fort Bend County Sheriff's Office believes it was an accidental shooting that happened around 10:30 p.m. Monday inside a home in the Mission Bend neighborhood.
Deputies arrived at the home on Great Oaks Shadow Drive near Paso Hondo Drive and found the victim alert and conscious. He was taken to the Medical Center for treatment.
The 13-year-old is expected to survive. Deputies said he had a gunshot wound to his abdomen.
Investigators said the 18-year-old accused of firing the shot left the scene, but was brought back to the home by the victim's brother.
Two guns were found inside the home, deputies said.
"From our preliminary information, it appears there was a tussle over the gun. Not sure if it was playing or there was an altercation. The shooter, his finger ended up getting inside the trigger guard. The gun discharges." Sgt. Phil McGuigan said.
The 18-year-old suspect was detained and charges will be decided by the Fort Bend County District Attorney's Office.
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