Melynda Davis now faces a murder charge, in addition to charges of injury to a child and tampering with evidence.
Little I'yanna Allen was found dead on Nov. 29, 2020. She was 4 years old.
ORIGINAL STORY: Woman charged in death of boyfriend's 4-year-old daughter
"The injuries were horrible," said Assistant District Attorney Gilbert Sawtelle. "They were unthinkable."
According to court documents, the child had lacerations and whip marks all over her body. They believe Davis also used an ammonia soaked towel to suffocate the child.
"She had burns all over her face and strangulation marks under her neck," said Sawtelle.
Sawtelle said phone records helped investigators piece together the case, and the result of an autopsy report is what helped them seal the murder charge.
According to the Montgomery Country Medical Examiner's office, who conducted the autopsy, this long period is standard when it comes to dealing with a pediatric autopsy report.
SEE ALSO: Houston mom gets 8 years of probation after pleading guilty to 2017 death of 9-year-old son
Prosecutors say there was never a doubt that they would not get the murder charge eventually. They were already working with strong evidence.
According to court documents, Davis texted the child's father and told him she was going to discipline the girl because she had wet herself. Further searching through Davis' phone records detailed even more about what she allegedly did to her stepdaughter.
"She's looking up Google searches on how to deal with ammonia bruises, whether or not someone can inhale ammonia, and how to treat that," said Sawtelle.
Prosecutors believe that Davis had been abusing the child for months before her death.
For updates on this case, follow Stefania Okolie on Facebook, Twitter and Instagram.