Wyatt's mum Angie helped her elderly mum to the car as she was recovering from a broken leg. When they got to the car, the tyres were burning.
"The flames were all around it and around the car," Wyatt's great aunt, Mary Tofte, told the local TV station.
Meanwhile, Wyatt's dad Chris was desperately trying to get back home to rescue his family, seeing the fire had headed in their direction.
He passed a few roadblocks frantically driving home and spotted a badly burnt woman crawling along the roadside. He stopped to try to help her but told her he couldn't take long as he needed to try to get to his family.
As he helped the woman into his car, telling her he needed to go save his son and wife, the woman whispered that she was his wife.
He drove to a checkpoint and left his wife with the paramedics then drove towards his house to find his son. However, it was too late.
Authorities and relatives believe the 13-year-old tried to drive the car to save himself, his grandma and his dog Duke.
He managed to get down the road but then the car was found off to the side of the road. Officials believe the hot asphalt burnt the tyres and the car ended up caught in the inferno.
A GoFundMe page has been set up to help Wyatt's mum Angie recover. She suffered critical burns while escaping the fire.