Prosecutors filed a sexual assault charge Thursday against the mother of a three-year-old Aurora girl who was found dead after what police described as a severe beating.
It was the first public indication the child may have been sexually attacked.
District attorney's spokeswoman Kathleen Walsh said she could not discuss specifics of the allegation.
Thirty-four-year-old Susie Ida Quartey faces charges of sexual assault on a child by someone in a position of trust, assault with a deadly weapon and child abuse-knowingly causing bodily injury.
Walsh said the investigation remains open and additional charges could be filed after police receive the results of toxicology tests from the coroner.
She said she could not discuss whether homicide charges were a possibility.