What started as a trip through the drive-thru quickly turned into a life-saving mission for an employee at the Pal's on Volunteer Parkway in Bristol on Tuesday.

A customer was in line waiting for her food, but in a flash, that all changed.

"She told us, 'somebody help me, he's not breathing,does anyone know CPR,'" Pal's employee Kaela Eads said. "Well my first instinct, in a blink of an eye, is to go."

Surveillance video shows the mother rushing to the window asking for help because her toddler wasn't breathing.

The next thing she knew, Eads sprung into action, giving the seemingly lifeless child CPR and eventually reviving him.

"He would breathe for me for a second and then he would stop," Eads said. "I would continue again and then towards the end, before the ambulance got here, I got him to breathe constantly, but it was very faint."

The 18-year-old learned CPR in high school and never thought she would use her training, but emergency workers, who were there within minutes, told Tri-Cities NBC-affiliate WCYB it helped save a life.

"Just knowing that something was wrong and they stepped into action and did what they felt needed to be done did make a difference," Steven Carroll from the Bristol, TN Fire & Rescue said.

After work, Eads eventually headed to the hospital that night to check on the little boy. She told us he seemed to be doing well as he watched cartoons.

"It's something I'll remember forever," Eads said. "That blank stare in his eyes whenever I first started to seeing him in the hospital was a total change and it was amazing."

Eads said she just started the morning shift and had this been a day later, she wouldn't have been working.

She also said after this night a lot of her co-workers want to get CPR certified.