The wreck happened about 3:30 p.m. along NC 24/87 near Olivia Road (SR 1205).
That's near the Olivia post office, south of the Harnett County-Lee County line.
State troopers said a 2017 International tractor-trailer was traveling north on NC-24/87 and failed to reduce speed when a 2026 Hyundai Palisade SUV was stopped at a red light.
The truck rear-ended the Hyundai, pushing it across the intersection and into a 2008 Chevrolet Tahoe that was stopped facing south in the turn lane.
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After the impact, the Hyundai veered off the road to the right. The other two vehicles came to rest in the roadway.
The driver of the Hyundai was taken to Cape Fear Valley Medical Center in Fayetteville with life-threatening injuries and was life-flighted to UNC-Chapel Hill.
An 8-year-old boy in the backseat was pronounced dead at the scene.
A 9-year-old girl in the front seat was also rushed to Cape Fear Valley with life-threatening injuries and then life-flighted to UNC-Chapel Hill.
The driver, a passenger, and an infant in the Tahoe were taken to Central Carolina Hospital in Sanford with minor injuries.
The truck driver, David Allen Cuellar, 63, of Lake Station, Indiana, was not injured but was charged with misdemeanor death by motor vehicle and taken to the Harnett County Jail.
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