The shooting happened in Chicago's Marquette Park neighborhood in the 3000-block of West 64th Street at approximately 10:35 p.m. Tuesday. The mother, identified as 17-year-old Charinez Jefferson, was shot in multiple times in the body, in addition to the gunshot wound to her head.
A vigil was held at the scene of the shooting on Wednesday night.
Hospital officials said the baby, a boy, was in critical but stable condition Wednesday. Family members said he was fighting for his life and not breathing on his own, but they were hopeful he would survive.
"The baby at this point, he is fighting for his life," said Charinez Jefferson's mother, Debbie Jefferson. "He's not breathing on his own."
Charinez Jefferson had a 1-year-old son and was about to be a junior this year at Banner Therapeutic Day School on the city's South Side.
"She was a great mom. She was young, but she was a good mother," said Debbie Jefferson.
She added that she did not believe her daughter was the intended target.
"I loved my little sister. I'm going to miss her. This has got to stop," brother Pierre Jefferson told ABC7 Chicago as he held his crying mother.
While loved ones struggled to cope with the loss of the mother, police were trying Wednesday to find out who shot the teenage mother and why.
"I had just talked to her maybe two minutes before the shooting. She said she was on her way to the house. She never made it," said Debbie Jefferson.
Police say the 17-year-old girl went to a neighborhood corner store Tuesday night and stopped to talk to a group of friends when a car approached and a gunman got out and started shooting. The teen mother-to-be was the only person hit as others scattered.
"It just has to stop, and she being pregnant, it was really sad that they actually shot a pregnant woman that many times," Debbie Jefferson said.
Paramedics said they found Charinez Jefferson in full cardiac arrest and performed advanced life support treatment as they took her in critical condition to Advocate Christ Medical Center in southwest suburban Oak Lawn. Jefferson was pronounced dead at the hospital shortly after 11 p.m. She was six months pregnant.
"A decision was made by the doctors caring for the patient coming in to attempt to care for the baby and give it the best options," said Dr. Brian Sayger of Advocate Christ Medical Center.
A doctor said that a priority is ensuring that the baby is receiving enough oxygen, but in this case, despite their efforts, the baby was deprived of oxygen for a period of time. Doctors said some health issues may result.
"Once we've determined that the mother is no longer viable, the main focus is delivering that child and attempting to give that baby the best chance of life," said Sayger.
Throughout the day, Jefferson's relatives and friends gathered at a growing memorial, where they described the teen as outgoing and a doting mother.
"Charinez was, before anything, she was a mother and a young lady," said friend Jajuan Moore. "She was a mother before anything."
"She was definitely a wild child, but after she had her firstborn, she changed for the good," said cousin Terrisha Williams. "She put him first."
No arrests had been made Wednesday as police continued to investigate the motive for the shooting.
