CHICAGO (CBS) — An 18-year-old girl was shot and killed while walking down the street Sunday night in the Back of the Yards neighborhood.

Treja Kelly was a straight A student who had plans to go to college, according to her grandmother, Judy Fields.

Fields told CBS 2’s Mugo Odigwe that she has lost three grandchildren to gun violence.

“My grandchildren are very dear to me, and I’m losing them,” Fields said.

Treja Kelly, 18, was shot and killed near 52nd and Sangamon on Sept. 8, 2019. (Source: Facebook/Treja Kelly)

Police said Kelly was walking near 52nd and Sangamon around 9:30 p.m., when a man walked up from an alley, and the two of them got into an argument.

The man then pulled out a gun, and shot her several times in the head and chest.  Kelly had just gotten off the bus after work and was walking home, Fields said.

“I heard the shooting, and I came out on the porch and I saw everybody running,” Fields said.

Kelly was taken to the University of Chicago Medical Center, where she was pronounced dead, according to police and the Cook County Medical Examiner’s office.

Police said the man ran away after the shooting. No one was in custody Monday morning.

Area Central detectives were investigating.

“I don’t understand why they can’t stop these people from doing all these shootings,” Fields said. “Protect the kids some kind of way.”

Despite the pain of knowing she will never see her granddaugher again, Fields said she’s trying to stay strong for Kelly’s mother and two siblings.

“You just have to pray about it and ask God to give you strength.”