Harris County Sheriff's deputies say Melissa Pharris, 31, and her two children were driving westbound on FM 2920 at Hagar around 8:30 p.m. when they were involved in a head-on crash with a Cadillac.
Police say Pharris attempted to pass multiple vehicles on the left in a no passing zone.
The Cadillac then struck a Hyundai SUV with a woman and her 2-year-old child inside. They were not hurt, but the driver of the Cadillac, 81-year-old Bernice Johnson, died at the scene.
Deputies say Pharris was taken to the hospital by ambulance. She is expected to survive her injuries.
Her two children, a toddler and a 14-year-old, were taken by Life Flight to the hospital in critical condition, but they too are expected to survive.
Investigators said the driver of the minivan admitted she had taken Tylenol before the crash, but deputies said they believe she was under the influence of stronger prescription drugs based on the way she was acting at the crash scene.
The Harris County Sheriff's Office says Pharris has not been cooperative during the course of their investigation.
Deputies are awaiting a toxicology report to see if she will face charges.
Pharris may be charged with intoxication manslaughter if she is shown to have been impaired by the drugs, according to deputies.
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