The woman, identified as Jasmine Denise Reese, was shot at about 2:45 a.m. -- minutes before arriving at her friend's house with a group of people in the 7200 block of South May Street, police said.
Reese was killed by a bullet that flew through the window.
Police said the shooting was sparked by an argument that had just taken place. Reese's friend was filling her and her boyfriend in on what had happened as they settled down on a couch that was facing the window.
Woman fatally shot in head in Englewood, police say
"She was saying something about how her shoulder hurt because they were fighting. Her boyfriend suggested they leave and she was like ok. But just moments after that," said Reese's mother, Stephanie Seaton.
Reese was pronounced dead at the scene, police said.
No one is in custody.
Earlier that night, Reese told her aunt, Angela Coffey, that she and her boyfriend wanted to move to Indiana. She wanted to go back to school and become a corrections officer.
"Somebody needs to come forward. I know people don't want to talk and they don't want to get involved but this was an innocent life. Someone needs to say something," Coffey said.
Chicago police are investigating the shooting.