GALVESTON, Texas (AP) -- Court documents say the mother of two year-old Riley Ann Sawyers told police she and her husband beat the girl with two leather belts and held her head underwater in a bathtub.
The documents say Riley's stepfather then threw her across the room, slamming her heat onto a tile floor.
Kimberly Dawn Trenor said in her statement to police that the couple bough a plastic bin and placed her daughter's body inside it that evening.
Trenor's statement says it was a month or two before they dumped the bin into Galveston Bay.
The couple then told family that social services took Riley.
A fisherman found the bin last month and authorities spent weeks sifting through thousands of leads as they worked to identify the girl they dubbed "Baby Grace."
Meanwhile, court documents show the stepfather, Royce Zeigler, attempted suicide last week.
He left a note saying his wife was "innocent of the sings" he'd committed.