The girl, who has become known as "Baby Madison," was found off of Interstate 45 on Sept. 17, 2016. Her body was wrapped in a trash bag and placed inside a black suitcase.
Sgt. Chelsea Stanford with the Madison County Sheriff's Office said testing has revealed that the girl is believed to be between two and five years old. Along with her remains, a long-sleeved pink dress made by "Mon Petit" in a size 4T was found in the bag. She was also wearing a size 4 diaper.
A feeding tube was found in the bag, indicating she probably required specialized medical care.
Thursday, investigators said they had done genetic testing on her remains that showed she likely had ancestral ties to El Salvador and Nuevo Leon, Mexico. She is also believed to have had long, thick black hair.
Originally, investigators believed that "Baby Madison" had the medical condition micrognathia, which causes the lower jaw to be smaller than normal. Now it is believed she did not suffer from the condition, which has led to the new image of her face.
SEE ALSO: Previous composite image of little girl's face
Do you know the little girl with the feeding tube?
Supervisory Special Agent Charlie Wilks with FBI Houston said they do not know how or where she died. Authorities are not sure that her death occurred in Texas.
RELATED: Autopsy reveals details about child found in trash bag near I-45
Authorities said they have received numerous tips throughout their investigation. Some pointed to Arizona. They said they have been able to rule that out.
"Baby Madison's" remains are still at the medical examiner's office as they work to identify her.
If you have any information about "Baby Madison's" identity, you are asked to call the Madison County Sheriff's Office at 936-348-2755.