The 13-year-old was shot as he ran errands for troops.
The family of the boy, who was 12 when he was wounded in the stomach, claim he suffered three fractured vertebrae and spinal injuries.
It is alleged the boy was shot outside a British barracks last September after soldiers gave him money to go to shops and buy them a crate of cola.
The MoD confirmed that Private Alexander Johnston will be questioned about the incident.
The boy is being treated in hospital in Sheffield and is said to have paralysis of his legs.
The family claim the boy's injuries were as a result of "negligence" and say the soldier had failed to ensure the safety catch on his gun was engaged.
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