A 3-year-old boy from Ross was killed yesterday on a Georgia interstate when a tractor-trailer smashed into the back of his family's minivan.

Sean Thornton died at the scene in McIntosh County, 45 miles south of Savannah. His parents and two siblings were badly injured and being treated at a hospital in Savannah.

The Georgia State Patrol did not return calls seeking comment about the crash.

But according to numerous media reports, police said the family was traveling to Florida for the holidays when they came across heavy traffic on the interstate at about 12:30 p.m.

Susan Thornton, 38, had slowed the van to about 5 mph when an 18-wheeler hit the vehicle from behind at an estimated 70 mph, according to witness accounts. The truck pushed the van off the highway and into the woods, where the vehicles knocked over several trees.

Sean was in a car seat, but the impact killed him.

His sister Sarah, 5, and brother, Christopher, 8, were also restrained in the van. Both were injured and flown to Memorial Health University Medical Center in Savannah along with their parents. A hospital spokesman said the facility does not release the conditions of children, but police said neither child suffered life-threatening injuries.

Susan Thornton was listed in critical condition yesterday. Her husband, Daniel E. Thornton, 47, was in good condition.

The trucker, Willie Hill, 50, of Jacksonville, was also being treated at the same hospital for a broken leg and pelvis.

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