Detroit,MI (CBS) - General Motors said last week that it was recalling more than 700,000 vehicles because of a problem with the ignition switch.
GM said six people had been killed in accidents.
But CBS News has learned GM's recall is coming 10 years after the defect was first discovered and seven years after people began to die.
On Oct. 24, 2006, a compact car went off the road in St. Croix County, Wis.
Two teenagers were killed: 18-year-old Natasha Weigel and Margie Beskau's 15-year-old daughter, Amy.
"There's days that I am fine, days that I can function," Beskau said. "But there's just as many bad days where you just want to cry all day."
There was no drinking involved, no other cars on the road. Weather was determined not to be a factor.
No one was wearing a seat belt, but an investigation found the airbags never deployed, and the ignition switch was found in the accessory position, meaning the car likely did not have power when it crashed. No power steering, no power brakes, no airbags.
Natasha's stepfather, Ken Rimer, has spent the last eight years looking for answers.
"Every day we go: 'I wonder what happened?'" he said.
No one has ever told him.
The girls were in a 2005 Chevrolet Cobalt, a vehicle included in that massive recall of more than 700,000 cars just last week, because GM says a heavy key ring or sudden jarring can switch the car off.
Now, in a letter sent to the Department of Transportation by the family of another person who died in a Cobalt - a 29-year-old nurse in Georgia named Brooke Melton - lawyers charge GM knew about the ignition defect in 2004.
A service bulletin was posted to dealers by GM in 2005 in case customers complained, saying "there is potential for the driver to inadvertently turn off the ignition….the concern is more likely to occur if the driver is short and has a large and or heavy key chain."
But the cars kept being manufactured, without a fix, and none were called back.
Joan Claybrook is the former head of the National Highway Traffic Safety Administration.
"This is an immoral act by General Motors to cover up this defect, not tell people and then the result was inevitable, that people were going to die and be injured and that to me is unconscionable," she said. "It's like throwing an airplane passenger out without a parachute."
CBS News asked GM for a comment on camera. The company declined.
When CBS News asked last week why the recall wasn't issued a decade ago, the company said: "The incident rate was very low with no growing trend."
It added today: "The safety of our customers is paramount. Given our present understanding of the 2005-2007 cobalt ignition switch torque capabilities, we have announced a recall."
Families who lost loved ones may be getting answers.
"It made me angry," Beskau said. "They knew something was wrong with the car before the accident. I just don't understand how they can knowingly put these cars out and still let people drive them. This is my child. This is my baby girl."
Natasha and Amy's deaths are two of six that have been linked to the ignition issue. The company stopped making the Cobalt in 2010, but there are still more than a half a million on the road.
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