"Hi, I just want to say we can't wait for you to arrive!" said Hardisty.
But soon after, she had a heart attack. A frantic situation got worse when her ambulance blew a tire and ended up on the side of the road. Amid the confusion, her breathing tube came loose. She didn't survive.
"It wouldn've have fell out if they didn't have to transfer her from one ambulance to another,'' says her son Mike Newton. "And she wouldn't have obviously died because of lack of oxygen to her brain."
When that accident happened, Firestone Steeltex tires were already blamed for many unusual failures on rescue vehicles -- when seconds count. Now, a CBS News investigation has found 82 rescue squads in 26 states reporting problems.
The federal government has twice investigated Steeltex tires and found no defect – even saying their failure rate is lower than competitors. But consumer groups lambasted that decision. And now a class action suit is being fought for owners of Steeltex tires on millions of rescue vehicles, light trucks and RV's.
Under the lawsuit, Firestone must preserve certain damaged Steeltex tires for experts to inspect.
But experts will never get a look at some of these tires, judging by pictures obtained by CBS News. They were in line for shredding at a different company's facility, which happens to be next door to Firestone's plant in LaVergne, Tenn.
So what is Firestone saving? Only damaged tires that customers themselves ship directly to headquarters. The problem is, most customers don't know to do that.
Joe Olmsted of North Syracuse, N.Y., had no idea there was a lawsuit. So when his ambulance had two tread separations in one night with patients aboard, he didn't send the tires to Firestone headquarters. He scrapped them.
"The tread separated approximately right here, this all came apart,'' Olmsted said, showing Attkisson a tire.
Consumer advocate Joan Claybrook of the group Public Citizen says not collecting all the damaged Steeltex tires is a missed opportunity to get to the bottom of any problem.
"Our view is that these lawsuits are very important to the American public. They could get a lot of information they don't otherwise have access to quite easily," says Claybrook.
Matthew Newton won't ever get to know his grandmother; he was born just a few days after she died. And his parents can't help but wonder if things might have been different if only the ambulance had different tires.
"She definitely could be alive right now,'' said Mike Newton.