The girl has been identified to the Cook County Medical Examiner's Office as Angie Monroy. Monroy was a junior at Benito Juarez Community Academy.
"I feel broken," said Joselyn Monroy, victim's sister. "Like they took a piece of me. And that I'm not going to ever get it back."
Angie Monroy was a cheerleader at the Pilsen high school, and the youngest of her siblings. She had just recently taken a job at a clothing store about half a mile away from her home in Little Village.
Police said Monroy was walking in the 2300-block of South Rockwell Street on her way home from work at about 9:43 p.m. Saturday when she was shot in the head. Police said someone on the street heard gunshots ring out and saw Monroy on the ground.
"We told her, you don't have to work. Just study. Go do what you do best right now. But she said no. She wants to help out. She wanted to have her own stuff and be able to have her own things without asking her parents," her sister said.
Police said the teen was transported to Mt. Sinai Hospital in critical condition. She was pronounced dead Sunday morning, the medical examiner's office said.
Monday police released a picture of what they say is a 2000 to 2002 beige Toyota Tundra that was seen circling the neighborhood in the moments before the shooting.
Joselyn said it was not like her sister to walk home at night. She said about 15 minutes before her sister was shot, she got a text from Angie saying she'd be getting a ride home from a coworker. An hour later it was a detective, not Angie, who answered her phone.
"She was caring. Loving. She would never hurt a soul. Never," said Steven Monroy, victim's brother. "The fact that you took her away from us, it's evil. It's horrible.
Laura Hernandez called Monroy a close friend, someone who made their school day brighter.
"Brought joy around the school," she said. "Whether you knew her or not, she'd stop by, she'd say hi, she'd smile. You know? She was just somebody who brought that energy around everyone."
Students came to class Monday without that glow.
"She was a cheerleader, she played soccer, she played basketball, she did a lot here," Hernandez said. "Put a lot of spirit in a lot of people's hearts."
Mourners lit candles in her memory on the sidewalk where she was shot.
"How careless these people are about how many families are destroyed and we gotta do something, we've gotta keep going forward," Hernandez said.
No one is in custody in the shooting. Area Central detectives are investigating. Chicago police have stepped up uniformed and plain clothes patrols in the wake of the shooting.
Monroy's death is the latest in a recent rash of violence in the Southwest Side neighborhood. Last month, nurse Frank Aguilar was shot to death near his family's home in what authorities said was a case of mistaken identity. On Halloween, a 7-year-old girl was wounded by stray gunfire while trick-or-treating on a street bustling with children.