CHICAGO (CBS) — Six-year-old Aubrey Broughton is a fighter – and was home Thursday night after being this past weekend while sitting in a parked car in the Belmont Central neighborhood.

Her 7-year-old sister, Serenity, did not survive. And as CBS 2’s Charlie De Mar reported, the girls’ grandmother has been reliving that horrible night.

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Serenity And Aubrey Broughton

Serenity (left) and Aubrey Broughton. (Supplied by Regina Broughton)

Chicago Police Chief of Patrol Brian McDermott said at 2:50 p.m. Sunday, police were called to the 6200 block of West Grand Avenue, at Merrimac Avenue, for a ShotSpotter alert.

At the scene, officers found the two little girls, who had suffered multiple gunshot wounds, in a vehicle parked on the street. The officers rendered first aid until Chicago Fire Department paramedics came and took the girls to the hospital.

Serenity was shot in the chest and torso, and was pronounced dead at Loyola University Medical Center in Maywood.

Aubrey was shot in the chest and right armpit, and was also taken to treated at Loyola. Four nights later, she was home.

“When I do go to sleep, I see my granddaughter,” said the girls’ maternal grandmother, Mary Ivy.

Serenity and Aubrey had spent the day with Ivy on Sunday. As the girls began to leave with their family, someone pulled up and started shooting into the car.

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On Sunday evening, the girls’ paternal grandmother, Regina Broughton, told reporters that when the shots flew out, her son – the girl’s father – was on the driver’s side of the car while their mother had just finished buckling Aubrey in. At that point, the shots rang out, and Serenity was lifeless, Broughton said Sunday.

“The monster that did this to my granddaughter – I want them caught,” Regina said. “It could have been my whole family, because they were all in the car together.”

A vigil for the family was held Thursday night in the Belmont Cragin neighborhood.

“Why? My question is why?” Ivy said.

D’Kari Ivy, Serenity and Aubrey’s older brother, spoke at the vigil.

“She was a great sister, and she will be missed, and she’s in a better place,” he said of Serenity.

“But I’m still missing my Serenity,” Ivy added.

The family said despite everything they have gone through, Aubrey is in good spirits. They described her as a fighter.

Aubrey and her parents are staying with relatives. They are just not ready to go back to their home yet without Serenity.

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No one was in custody Thursday night in the shooting.

Charlie De Mar