The article doesn’t make it clear whether the boy who was shot has any connection to the ex- (plus all co-residents) the woman wanted to shoot.
Another report of the incidents had a bit more info. “She” (if that really is a cis-female) had earlier threatened to kill her ex-boyfriend “and his child.” That was the first arrest for harassment. She bonded out and went back and did the drive-by, hitting the 12-year-old — presumably the ex’s kid. She was seen by a neighbor riding around in the passenger seat of a Caddy “with a silver gun.”