DADE COUNTY, GA. (WRCB) -- Raul Fletes, 28, and his wife Michelle, 27, had been Robert & Marlene Bell's neighbors for a couple of years.

But when the Georgia State Patrol came knocking in Rossville's Duncan Park subdivision Saturday evening, "it just come as a shock," Marlene Bell says.

"I just immediately began to cry," her husband says. "And regret that I hadn't gotten to know them better."

"I can't imagine what happened for them to hit that 18-wheeler," neighbor Marvin Dotson adds.

The GSP reports the couple died when their Dodge Charger slammed into the rear of a big rig, and went up under it, on I-59 near the construction zone interchange with I-24 right outside Trenton about 2 o'clock Saturday afternoon. Michelle Fletes was driving.

"She had to have been going 75 to 80 miles an hour," trucker Charles Dicesari told Channel 3. "From the speed that I was going and how fast they passed."

"They had to have on cruise control and fallen asleep," Dotson insists. "They were too careful."

But he, the Bells and Michelle's uncle, Anthony Provancher are certain why 3-year-old Tayen Fletes survived.

"If the impact had hit a few inches more, then they would have been grieving for her too," Marlene Bell says.

"If she hadn't been strapped in good," Dotson says.

"Snug in her car seat, which most assuredly saved her life," Provancher writes on Facebook.

Erlanger's LifeForce helicopter crew confirms Tayen was in her safety seat when rescuers reached her.  Michelle Fletes' Facebook page displays prominently, a picture of her daughter in that seat.

"It's the tight fit of those seats that puts them in pre-crash position," says Coy Ellis, a registered nurse with the Kohl's Safe and Sound program at T.C. Thompson Children's Hospital.

"Part of that is putting them in the safest place in the vehicle."

Tennessee, Georgia, Alabama and North Carolina all require infants, toddlers and children be placed in special restraint seats or booster seats when passengers in motor vehicles. Tennessee's law applies through age 9; Georgia's and North Carolina's through age 8, and Alabama's through age 6.

"Rules differ for age and weight," Ellis says. 

"For example, infants, up to age 2, are strapped in, on the second row bench or bucket seat, facing the rear of the vehicle."

But toddler seats are strapped in facing forward, and preferably, in the center of the bench seat.

"Many crash injuries are crushing injuries," Ellis explains. "A head-on collision will push all that weight back. If your safety seat is directly behind the front passenger seat, it, and whoever's in it, will be pushed back into your child!"

The GSP hasn't specified where investigators found Tayen Fletes in the wreckage. As of Monday evening, she was listed in fair condition at Erlanger-Children's Hospital.

Dotson worries for the little girl's spirit.

"How are you ever going to explain that your mom and dad aren't coming home anymore," he asks.

"She seems to be in severe shock and probably witnessed a horror that most people can only imagine," her Great-Uncle, Anthony Provancher writes on his Facebook page.

"Lord, most of all, please comfort Tayen. May the sparkle in her eyes return in time."

To find out more about Child Safety Seats and whether you've installed such restraints properly, click here.