CBS Denver reported the brother was the driver when the kids took off in the Dodge Durango early Monday morning, and went about three miles, before ramming into a light pole and rolling the vehicle, twice.
The children's aunt, Kelly Stewart, said the boy stole the car keys on Sunday and drove off with his sister around 1:30 a.m., hours after their mother put them to bed.
“(She) Didn’t hear anything until the cops knocked on her door,” Stewart said.
According to the station, the boy panicked upon seeing a police car, lost control and crashed. The SUV was smoking when officers arrived.
CBS Denver said both children were taken to the hospital with head injuries but are expected to fully recover.
Their aunt says despite the dangerous adventure, wearing seat belts was probably their salvation.
Colorado Springs police say they don't plan to file any charges, CBS Denver reported.