Aireon Luster is charged with murder for the death of Serenity Broughton and with attempted murder for the injuries her 6-year-old sister Aubrey suffered.
RELATED : 'She didn't even get a chance to fight': Family grieves after 2 sisters shot, 1 fatally, on NW Side
During his bond court appearance, prosecutors said Luster threatened a rival gang member in Facebook live half an hour before showing up at a Northwest Side home with two other men and opening fire. Several shots went through a car there, where Serenity and her sister were waiting for their family.
The sisters' father said his family had stopped by to visit relatives in the 6200-block of West Grand Avenue after Sunday church services on Aug. 15. They had wrapped up their visit just before 3 p.m., and were going to pick up food and head home -- with the girls already in the car -- when the shooting happened.
"They shot her in her heart. She didn't even get a chance to fight," Michael Broughton, the girls' father, said.
"We believe they were not the intended targets. We believe they were shooting at a relative who was part of that house," said Chief of Detectives Brendan Deenihan.
Aubrey was struck in the chest and right armpit, and was hospitalized in critical condition, though she later stabilized.
CPD Superintendent David Brown said Luster was taken into custody Wednesday in the basement of his grandmother's home in suburban Riverside. He is due in bond court Thursday.
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This is actually the second time police have arrested Luster in this case; the first time they were forced to release him when the Cook County State's Attorney's Office declined to file charges, saying they needed more evidence.
The case put police and prosecutors at odds. The district commander sent an internal email to staff saying he was extremely proud of the work done on the case, and that the case should have been charged.
Prosecutors presented numerous pieces of evidence against Luster Thursday, including 29 shell casings gathered at the scene and video they said shows him and two other men getting out of a car Luster owned. Prosecutors also said three witnesses have identified Luster from pictures connecting him to the scene, and that cell phone records place his phone near the scene at the time of the shooting.
Serenity's family released a statement saying in part, "We are excited and this moment is bittersweet, justice for our family is all we hoped for."
Prosecutors say Luster was on parole for attempted armed robbery at the time of the Serenity's murder. The judge ordered him held without bond.
Brown said he hopes the charges can be the beginning of giving the family "some measure of closure" in the death of their daughter.
Chicago police said they are still trying to find two additional suspects they believe were involved in the murder.