The SUV crashed into a tree and caught fire in the vicinity of Bear Valley Parkway and Bear Valley Road, south of state Route 78, around 8:50 a.m., according to California Highway Patrol Officer Jim Bettencourt.
A 62-year-old man from Escondido stopped and attempted to get the 37-year-old driver, identified as by San Diego Medical Examiner as Arthur Walker, out of the vehicle.
"When he realized that he could not get the driver out of the vehicle he focused on a 2-year-old in his car seat in the back," Bettencourt said. The man proceeded to perform CPR on the child until emergency crews arrived, according to CHP.
The child was taken to Palomar Medical Center, but later died, Bettencourt said.
CHP determined the two people who died in the crash were father and son.
"Our hearts certainly go out to the family and the good Samaritan who was on scene, who had to witness something I’m sure they never expected that they would witness on a day like today,” said Bettencourt.
It was unknown what caused the SUV to veer off the road and if drugs or alcohol played a factor.