Authorities say Jaylyne Doramus was fatally ejected from a Ford Explorer in the rollover crash Thursday night.
Kane County sheriff's officials say Doramus was one of three people headed from Kanab to the Deer Springs Ranch area.
The 47-year-old driver, Tanya Sales, was also ejected but survived and was able to make it back into the vehicle with the help of 55-year-old passenger Gary Cross.
The two remained in the car during the rainy night. When the sun came up, they found a deactivated cell phone among the wreckage and called 911.
They were taken to the hospital.
Officials say Doramus' 2-week-old baby was safe with its father when the crash occurred.
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