The stolen car hit the family's car outside of Terminal 2.
Caleb is struggling to survive. His 5-year-old brother Evan is in critical but stable condition.
Their mother is also in the hospital.
The family had just returned to St. Louis from a trip to Disney World. Their aunt, Brittany Lee was able to leave the hospital Tuesday night and spoke with FOX 2 news.
The SUV sped away from Normandy police during a traffic stop. It had been stolen in a carjacking in St. Louis city. Three juveniles were inside, a 16-year-old boy, 15-year-old boy and a 15-year-old girl. They had minor injuries in the crash and were taken into custody.
The victims' family believes it was dangerous for police to chase the stolen SUV near the airport.
They've set up a GoFundMe page for medical expenses.