Robeson County Sheriff Burnis Wilkins said deputies, U.S. Marshals and Lumberton Police took a 15-year-old into custody at the Budget Inn motel in Lumberton.
Authorities also searched a vehicle and seized two firearms and ammunition.
Nine-year-old Estrella Sosa was shot last Saturday while riding in a car with her mom.
Estrella was released from UNC Children's Hospital on Thursday.
The juvenile was charged with assault with a deadly weapon with intent to kill inflicting serious injury, assault with a deadly weapon inflicting serious injury, felony conspiracy and discharging a weapon into an occupied vehicle.
Law officers also arrested Joshua A. Locklear, 24, of Lumberton and charged him with accessory after the fact, possession of a stolen firearm and contributing to the delinquency of a minor.
Locklear was taken to the Robeson County Detention Center on a $100,000 secured bond.
Three others have also been arrested in the case.
Anyone with further information about this case is asked to contact the Robeson County Sheriff's Office at (910) 671-3170 or (910) 671-3100.