Mallett, 19, has just finished her freshman year at college and was confronted with the emptiness of having no family to go home to for the summer, said Caesar, of Orlando, Fla. She moved in with an aunt, Judy Smith, of Lithonia, Ga., he said, adding that she did not want to talk about the accident.
For Caesar and Smith, there was still the nagging question of why the truck driver walked "away from this tragedy without as much as a ticket. I need to know," Caesar wrote earlier this month. He said state police would say only that the matter was still under investigation.
Ainsworth Mallett was driving his family home to Stone Mountain, Ga., after a Christmas visit with his mother in Connecticut when their car was hit from behind on the pike. Mallett, 51; his wife, Jacqueline, 49; their 12-year-old son, Drew, and their small white dog ended up dead.
Nicole Mallett, who was dozing in the front seat, escaped with a cut lip and minor injuries, Caesar said.
Her father, who came from Jamaica, operated a Golden Krust Bakery & Grill, a Caribbean franchise restaurant, near their home. His wife was a secretary at a middle school. Their son was a football player and member of his school's band.
Sgt. Brian Polite, a State Police spokesman, said that a lengthy and detailed investigation revealed the tractor-trailer driver was not at fault. Instead, "a blond-haired woman" who was driving a white or light gold small sports utility vehicle farther up the turnpike is wanted for questioning, he said.
Polite said that the SUV had orange and blue New York plates and that this "mystery driver" had "stopped abruptly in the center lane of the turnpike, made a dead left, crossed the left lane and left shoulder, and then went through the separation in the median barrier" in order to turn around.
This caused the three vehicles behind her - a Ford Edge, the Camry, and the tractor-trailer - to slam on their brakes, creating a chain reaction that led to the fatalities, he said.
"It's a very reckless maneuver," Polite said. "There are other ways to get to the other side. They're called exit ramps."
The cut-throughs, dubbed Z-cuts by police, are reserved for law enforcement and emergency vehicles, he said.
"Oh, wow," said Caesar, when he learned of the mystery driver last week. "Now it all makes sense to me. I understand now why it happened and how it happened. It still doesn't take away the fact that my family is gone," but it helps.
Polite said accident reports are distributed only to people involved in an accident and their lawyers. But he also said state police issued an alert a few days after the crash to enlist the public's support in finding the SUV driver.
So far, he said, she has not been found.
Caesar said he was uncertain if his niece was aware of these details. He said that Jacqueline Mallett was his sister and that he had not seen the alert. Nor had another sister who lives in Atlanta, he said.
As for the SUV driver, he wondered out loud if "maybe she doesn't even know she caused what she caused."
The National Highway Traffic Safety Administration says that in 2011, the latest year for which statistics on fatalities have been compiled, 32,367 people were killed in 5.3 million crashes. Though excessive speed and alcohol and drug abuse were the leading causes, "operating vehicles in erratic, reckless or negligent manner" caused 2,604 driver deaths.
The agency collects detailed information so it can run "education campaigns and encourage better enforcement to continue saving lives" of drivers and passengers who travel the nation's highways, spokesman Jose Ucles said. Recently, there has been a focus on distracted drivers who use cellphones and cause fatalities, he said, but other factors, including carelessness, can be deadly.
In this accident, Polite said the investigation was still going on. He would not speculate on what charges the SUV driver could face, noting it is up to prosecutors whether the deaths can be attributed to "using an illegal cut-through" and recklessness.
Polite, who has responded to crash sites during 12 years as a trooper, said investigators spent hours reconstructing the accident and interviewing witnesses.
He said the report notes that the tractor-trailer was driving below the speed limit, had tried to steer left, and had used "basic evasive maneuvers to try to avoid striking" the Camry.
Nicole Mallett likely was spared because she was sitting in the front seat, on the right side of the vehicle, at the time of impact.
Caesar said that she told him she was dozing at the time and awoke to the sound of the crash.
He says there is a different reason she is alive. "It was," he said, "by the grace of God."
Contact Jan Hefler at 856-779-3224 or firstname.lastname@example.org, or follow on Twitter @JanHefler. Read her blog, "Burlco Buzz," at www.inquirer.com/BurlcoBuzz.