The crash happened along the Southwest Freeway at Gessner around 10:40 p.m. Wednesday.
Houston police believe the driver responsible may have been intoxicated and was actually fleeing from a previous wreck.
Investigators believe the driver took off from the scene of another crash and then ran a red light at the intersection, causing the crash with the mom and her kids.
The mother and her two kids were inside a Chevy Tahoe when they were hit by the driver, who was in a Toyota truck, police said.
The Tahoe ended up flipped over on its side, trapping the mom and her kids.
Bystanders and Harris County Precinct 5 constable deputies jumped in to help rescue the children from the car.
As for the mom, she was trapped inside the car and had to be rescued by Houston firefighters.
Everyone, including the driver of the Toyota truck, was taken to the hospital.