Amber Gibson (Courtesy: Hawkins Co. Sheriff's Office)

ROGERSVILLE, Tenn. (WVLT) -- Amber Gibson has been charged with First Degree Murder and Aggravated Child Abuse related to the death of three year-old Emily Barnard, the Hawkins Co. Sheriff's Office announced on Tuesday.

The toddler died in late July after what the Sheriff's Office described at the time as a devastating case of child abuse. Authorities suspected Gibson committed the abuse while she was watching Emily.

Judge John Duggar issued a gag order so investigators are not releasing the results of the autopsy or what led to the murder charge.

But Sheriff Ronnie Lawson says this is just one step and more charges could be ahead.

The girl's father, Erik Barnard, initially told authorities Emily had fallen and hit her head. Barnard and Gibson were reportedly dating at the time. Meanwhile, other family members told Local 8 News Emily's body was badly bruised and they did not believe her death was an accident.

Barnard had lost custody of Emily previously after drug charges against him, but at the time of her death, the girl was once again living with Barnard and Gibson.

Gibson's next day in court is February 3.