The victim's boyfriend, Isiah Alston, also 15, told reportes that Brandon was not the intended target.
"She was coming to see me," he said. "Somebody was shooting. It wasn't meant for her. That's my girl."
He said Brandon, who was with a group of friends, lived in Jamaica and was a student at Intermediate School 53.
Family members told 1010 WINS radio that Brandon was planning to attend John Adams High School in Ozone Park in the fall.
Police were still seeking Brandon's killer Sunday.
Six people were arrested in connection in the shootings a few hours later of five men near a restaurant at Beach 21st Street and Mott Avenue in Far Rockaway. A revolver was recovered from a jeep.
