Authorities say she was wading in Horsehead Cove at Lake Lugert with her grandfather on Monday when she stepped into deep water.
Her grandfather pulled her out and started CPR until paramedics arrived.
She was then taken by helicopter to Children's Hospital in Oklahoma City where she died last night.
Services for Taylor Hitchcock are pending through Lowell Tims Funeral Home in Altus.
She passed away Tuesday at an Oklahoma City hospital.
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