A woman who was engaged to the father of a toddler found unconscious at her North Texas home earlier this month has been arrested in connection with the 2-year-old's death.

On Tuesday afternoon, Plano police arrested 25-year-old Melinda Lynn Muniz. Muniz is charged with capital murder in the death of Lillian Grace Ford.

Plano police said Muniz is the fiancee of Ford's biological father and lived at the home where the toddler was found unconscious.

According to the Plano police warrant affidavit, on Jan. 9, officers were called to an apartment in the 1500 block of J Place by Ford's father, who said it sounded like his fiancee was being attacked and his daughter was screaming.

The affidavit states that the girl's father unlocked the apartment door and officers found Muniz face down on the floor of the apartment with her mouth duct taped. She claimed she had been sexually assaulted by an unknown man.

Police officers found Ford unconscious in the bedroom, her mouth had also been duct taped. She was taken to Children's Medical Center in Dallas for treatment and three days later, on Jan. 12, she was pronounced legally dead.

Police said the Dallas County medical examiner ruled Ford's death a homicide, the cause of death was suffocation.

The affidavit also states that Ford's maternal grandfather delivered a letter to Child Protective Services two days before the child's death stating that he was concerned about "physical injuries that Grace had suffered in the past." According to the affidavit, he said "the pattern began when Ford and Muniz moved in together."

According to the warrant affidavit, investigators found several inconsistencies in Muniz's recollection of the events on the day of Ford's death and lab results showed she was never sexually assaulted.

Ford's father told investigators he was breaking up with Muniz on the day of Ford's death and, according to the affidavit, that the pair had argued that morning.

The affidavit states that investigators traced Muniz's activities that day including a trip to a Dollar Tree store and obtained surveillance video from the store showing Muniz purchased duct tape similar to the tape found covering her mouth and Ford's mouth. According to the affidavit, Grace Ford was with Muniz at the store while the duct tape was being purchased. According to the affidavit, "This purchase was made 40 minutes before Muniz made the phone call to Ford in which Muniz claimed that she was attacked."

Muniz is being held in the Collin County Jail on $1 million bond.