"I thought, 'Oh, I popped a radiator,' " Childers, 61, of Addison, Texas, tells PEOPLE. "[Other drivers] going in the opposite direction are yelling at me, going, 'Get out! 'Get out!' "
She quickly stepped out just as the vehicle burst into flames.
As she waited for help to arrive, all she could think about was her 1-year-old Chihuahua named My Little Pony, trapped in his crate in the back.
"I'm standing on the side of the road and I'm dying because of her," Childers tells PEOPLE. "I'm going to die if this dog dies. I can't make it.' "
She made that clear when the Addison Fire Department firefighters arrived on the scene.
"I told them, 'I don't care about anything in it,' "she says, "you guys save that dog."
One team of firefighters had knocked out the windows and was working on extinguishing the flames when Capt. Scott Ledet and firefighter and paramedic Jake Metdker arrived.
Metdker headed to the RV to rescue the dog, with Ledet right behind him.
"Metdker couldn't see a foot in front of his face," Ledet, 47, tells PEOPLE. "It was completely smoked out."
Somehow he found the dog crate and handed it out to Ledet. Pony was "laying on her side," he says.
"Her eyes were fixed and open and she wasn't breathing or moving or anything," he says.
He took the crate to the side of the road and gently pulled her out to start CPR.
"I knew, in my opinion, she was dead," he says. "And I knew if I didn't do anything she was going to be dead."
So he started mouth-to-mouth resuscitation – something he never does on a human, let alone a dog – in addition to the CPR.
"I've seen stories where you do mouth-to-nose but she had soot and foam (coming out of her nose), succumbing to the products of the combustion and all, so I didn't want to do that," he says, "and honestly, just instinctively, I just opened her mouth and started breathing for her."
Courtesy Scott Ledet
He finally got her breathing and was able to hand the pup to its shaking owner.
"I won't say I never experienced that emotion before," he says, "but I almost felt like I was just going to break down and cry because it was a good feeling."
Childers, who works as a palm reader at the Magic Time Machine, a restaurant in Dallas, was left without a home (she parks it a local RV park) or her method of transportation, but she could not be more grateful.
"All I had burned down," she says, "but I'm okay with that because I have Pony."
Friends of hers have set up a GoFundMe page to raise $5,000 for her loss, while the American Red Cross set her up at the Motel 6 for a few days.
As for Pony, she's doing just fine.
"I call her the luckiest little miracle dog," Childers told a Dallas TV station.