The mother of Riley Ann Sawyers voluntarily told Texas authorities how she and her husband abused the toddler before the pair stuffed her body into a plastic box and dumped it into a Texas waterway, officials said today.
The chilling details of the abuse were outlined in an affidavit released Monday night.
"That was of her own volition," Maj. Ray Tuttoilmondo, a spokesman for the Galveston County Sheriff's Office, said this morning when asked on CBS' "The Early Show" how investigators had prompted Kimberly Dawn Trenor, 19, to admit to the couple's involvement in the girl's death.
Tuttoilmondo also told CBS that authorities are trying to determine whether or not Riley Ann was a victim of long-term abuse.
Monday, authorities in Texas announced they are "fairly confident" that the remains, discovered late last month by a Texas fisherman and nicknamed Baby Grace, are those of Riley Ann.
A positive ID cannot be confirmed until DNA test results are complete.
Authorities arrested Trenor and her boyfriend, Royce Clyde Zeigler II, 24, early Saturday. For now, the pair is being held on charges of injuring a child and tampering with evidence.
The pair could face additional charges including possible murder charges after a grand jury hears the case. Bail was set at $350,000 each. The couple could be in court as early as today.
The affidavit released Monday night quotes Trenor as saying the girl died July 24. In the affidavit, Trenor says Riley Ann was beaten with belts, had her head held underwater and was thrown across a room by Zeigler. Officials say the injuries to her skull identified during an autopsy were with that kind of trauma.
After Riley Ann died, Trenor said in her statement, Zeigler covered the child's body in a purple towel and then drove to a Wal-Mart to purchase items to hide and dispose of the body, including a blue plastic container, bleach, a shovel and latex gloves.
According to the affidavit, Trenor said Zeigler hid the container with the remains in a storage shed for two months before the pair tossed the container into the water off Galveston Causeway.
Trenor told police that Zeigler attempted suicide last week and wrote a note taking responsibility for the crime. "My wife is innocent of the sins that I committed," Trenor says the note read.
Tom Stickler, Trenor's attorney, has declined to comment about his client's statement, but he said Trenor has cooperated with police. He also said that from what his client has told her, "there is no doubt that the girl found is Riley Sawyers."
Neal Davis III, an attorney in Wendell Odom's law office, which is representing Zeigler, told ABC News that he had not seen the court documents released Monday night.
Davis described Zeigler as being from a middle class background and said he's never been in trouble with the law. "He has never been in the justice system before," Davis said, adding that his client, who worked in the oil industry, was "devastated."
Asked about Trenor alleging that Zeigler had taken blame for the death in a suicide note, Davis said he was not surprised. "I think when everything was falling apart for the two, he expected she would put all the blame on him," Davis said.
Officials say Trenor, who previously lived in Ohio with Riley Ann and the girl's biological father, Robert Sawyers, met Zeigler, a Texas native, playing the game "World of Warcraft" online.
Trenor moved to Texas to be with Zeigler in June, a few months after Sawyers was charged in a domestic assault incident with Trenor, his high school sweetheart.
The arrest of the couple comes nearly a month after a fisherman discovered the remains along the shore of a small island. Authorities released a composite sketch of a child they called Baby Grace and hundreds of tips from around the world poured into the Galveston County Sheriff's Office.
One of those tips was phoned in by Riley Ann's paternal grandmother, Sheryl Sawyers, who called investigators after she saw the Baby Grace sketch on the Internet. She told police Riley Ann had not been seen since July.
Trenor told relatives at the time that she gave the girl to someone who presented her with custody documents from Ohio that appeared legitimate.
In the affidavit released Monday night, Trenor changed her story, saying that after the girl was killed, Zeigler had her forge a document from the Ohio Department of Children's Services that stated Riley Ann had been taken away because of sexual abuse allegations.
Late last week, detectives requested DNA samples from eight families with missing children who resembled Baby Grace. One of the samples was submitted by Robert Sawyers, who still lives in Mentor, Ohio, the town where his daughter lived until her mother moved to Texas.
At a news conference Monday, Sheryl and Robert Sawyers wept while discussing Riley Ann. "It's hard to think that we'll never see her again," Sheryl Sawyers said.
Robert Sawyers described his daughter as a "fun-loving" girl. "There wasn't anything that she couldn't make," he said. "She had a very big imagination for such a little girl."