A man has been charged with two counts of attempted murder following the shooting of five-year-old Thusha Kamaleswaran and a 35-year-old man.
Anthony McCalla, 19, will appear in court on Saturday after the little girl and bystander Roshan Selvakumar were shot in a shop in Stockwell, south London, said police.
Police have also arrested a 14-year-old boy on suspicion of attempted murder in connection with the shootings.
A Met Police spokesman said on Friday: "Detectives investigating the shooting in Stockwell that left a five-year-old girl and 35-year-old man seriously injured have charged the man arrested yesterday and made a second arrest this afternoon."
McCalla, of Oakdale Road, Streatham, south London, will appear at Camberwell Green Magistrates' Court on Saturday charged with the attempted murder of Thusha and the attempted murder of Mr Selvakumar.
On Thursday a teenager targeted by gangsters who accidentally shot Thusha came out of hiding to help detectives find the gun attackers.
Relatives are maintaining vigils at Thusha's hospital bedside while detectives build up a "continuity trail" of the attackers' movements. Police said the child remains in a "critical but stable" condition, while Mr Selvakumar's condition is stable.
Meanwhile, beat police are beefing up their presence around Stockwell Food and Wine store as sources said up to 50 gangs are operating in the south London area.
Close family friend Velluppillai Navaratnam, 49, from Croydon, south London, said it was a "very difficult time" for Thusha's relatives.
"The parents of Thusha are at the hospital now," he said. "We are all praying for her to get well soon."