A three year old boy was killed Thursday when a driftwood log rolled down from a sand dune and struck him, Galveston County authorities said. Two of his relatives were injured.

LaShaun Lovejoy Huff and his family members were walking along a section of Crystal Beach near Monkhouse Road about 3:30 p.m. when a sand dune next to them shifted, officials said.

A log weighing several hundred pounds that was perched atop the dune suddenly began rolling toward the toddler.

LaShaun’s grandfather and a 15-year-old girl tried to prevent the 40-foot-long driftwood log from hitting him, officials said.

Sheriff’s deputies and paramedics used four-wheel-drive vehicles to move the log far enough to reach LaShaun, but he was pronounced dead at the scene, officials said.

The girl was taken to University of Texas Medical Branch at Galveston for treatment. She might have suffered broken bones from trying to stop the log, officials said. Hospital officials this morning said the girl, who has not been identified, was in stable condition.

The boy’s grandfather was injured but refused medical treatment, sheriff’s deputies said.

Although the investigation is continuing, officials said the boy’s family walking at the base of the fragile dune might have caused it to give way, sending the log rolling down at them.

The family had recently moved to Anahuac from Tennessee, officials said.