Police say the driver of a black car stopped, trying to avoid a mattress on the freeway, around 9:30 p.m.
When the black car stopped, it was rear ended by another car.
There were three children in the car, including the 6-year-old, according to authorities.
Police say the 6-year-old was not wearing a seatbelt at the time of the crash. The child was transported to the hospital in critical condition.
In the most recent update from authorities, the 6-year-old was in surgery.