Story highlights Sheriff: Mother charged with 2 counts of abandoning or endangering a child

Investigation determined children were left in a car for 15 hours, sheriff says

(CNN) Two young sisters died after after their mother intentionally left them in a car for more than 15 hours, Texas authorities said Friday.

The girls' mother, Amanda Hawkins, 19, was charged with two counts of abandoning or endangering a child, Kerr County Sheriff W.R. "Rusty" Hierholzer said in a news release.

Hawkins and a 16-year-old male friend initially took the children to Peterson Regional Medical Center in Kerrville, but the girls were found to be in "grave condition" and transferred to University Hospital in San Antonio, the release said.

Amanda Hawkins

Brynn Hawkins, 1, and Addyson Overgard-Eddy, 2, died there about 5 p.m. Thursday, the release said.

Authorities became suspicious after Hawkins told hospital personnel that she, the 16-year-old and the two children had been at a nearby lake, where the girls smelled flowers before collapsing, the news release said.

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