Three minutes into the video, there are gunshots, as the auto fired upon in an alley. One of those victims, an 11-year-old girl, died on Tuesday after she was removed from life support.
Police said the adult male victim was a known gang member.
The child was taken to the hospital where he later died.
Toddler Lavontay White was riding in a auto with his pregnant 20-year-old aunt Breunna Devonte and her 26-year-old boyfriend, who has not been named, when a gunman cut them off, got out of the auto and opened fire on their vehicle, the Daily Mail reports. "They killed him. I have a bullet in my stomach!" "I can't go. I can't go".
Lavontay White, identified by the Cook County Medical Examiner's office, was later pronounced dead in hospital. He was shot several times in the chest and was taken in a private vehicle to Little Company of Mary Hospital, where he was listed in critical condition. Family say she was about four months pregnant.
"They just don't fear it, and until we create that mental accountability to them to not pick up a gun, we're going to continue to see this cycle of violence", Mr Johnson said.
Earlier Tuesday, 11-year-old Takiya Holmes, one of two young girls shot on the South Side of Chicago over the weekend, died, according to her family.
Chicago Mayor Rahm Emanuel said the shooting should be a "turning point".
Johnson said that with "promising leads" and video evidence in the latest shooting, he had no doubt that those responsible would be caught. About three minutes into the livestream, the sound of a series of shots can be heard. Police say Jones has an extensive criminal record, including a pair of domestic battery charges last November. The chase ended at East 115th Street and South Doty Avenue in the city's Pullman neighborhood, near the Bishop Ford Freeway, police said.
"But it's just ridiculous that we have to keep seeing children pay the price because we can't hold these individuals accountable".