Houston police said Cathy Ann Gilley was behind the wheel of the Ford F-150 truck that slammed into a 75-year-old man's vehicle.
Investigators believe Gilley, who remains in the hospital, and her male passenger were both intoxicated.
ABC13's Charly Edsitty spoke to the son of the victim at the scene. He said his father was only three or four miles from home.
"They took my dad," Billy McGaha said through tears.
The crash happened around 2 a.m. Thursday on US-59 inbound at Greens Road.
Investigators say the rain was causing this man's windshield to fog up, and he was trying to get off the freeway. He was changing lanes when the truck slammed into the back of his Chevy Trailblazer, according to HPD.
The 75-year-old driver was pronounced dead at the scene.
The grandfather's three grandchildren - ages 8, 12 and 14 years old, suffered minor injuries and were treated at the scene. His family says he had just taken one of them to the hospital for chest pains.
"He took his granddaughter to the hospital because she had chest pains," McGaha said. "They saw her at Hermann and they were coming back."
All inbound lanes of the Eastex Freeway were blocked at Greens Road for several hours Thursday morning due to the crash, causing major delays.
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