The mother who died, along with her three children after a fatal car crash,  may have been speeding at 160km/h while driving under the influence of drugs, an investigation has found. Keisha Ann Jackson, from Wurtulla on the Sunshine Coast in Queensland, had been driving along Glenview Road with her four children on August 22 when her car slid off the wet road and slammed into a tree. The results of the toxicology  show the 30-year-old had cannabis in her system, which police believe would have affected her ability to drive, according to the Courier Mail. The preliminary results estimated the mother had driven between 130km/h and 160km/h  in a 80km/h zone at night.
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Toxicology results show Keisha Ann Jackson had cannabis in her system
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The mother and her three children died after a fatal car crash on August 22
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It's believed that the mother had driven between 130km/h and 160km/h in a 80km/h zone at night
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The 30-year-old mother and children, Ryan, 10, and Joan, seven,  died at the scene
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Matilda, 4, died later in hospital
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Eldest child Ethan, 11, escaped the wreckage with minor injuries and managed to flag down passing cars for help
@placeholder and four-year-old Matilda were found in the grass nearby and appeared to have been thrown from the vehicle upon impact.