A Kansas woman pleaded guilty Wednesday to murder and other charges in the abuse and death of her 3-year-old son, whose body was found encased in concrete in the laundry room of their Wichita home.

Miranda Miller, 37, pleaded guilty to second-degree murder, aggravated kidnapping, child abuse and aggravated child endangerment under a deal in which she faces a prison sentence of about 29 years. With credit for good behavior, she could get out of prison in about 25 years, District Attorney Marc Bennett told The Wichita Eagle after Miller’s hearing in Sedgwick County District Court. Sentencing was set for Jan. 14.

Prosecutors say Miller and her boyfriend, 41-year-old Stephen Bodine, tortured her son, Evan Brewer, for months before his death. Evidence against them included videos and photos showing Evan being abused, including footage of him chained and naked in a basement, being berated by Bodine and Miller, and forced to stand in a corner for hours. Much of the evidence came from a cache of 16,000 photos and video files collected by the couple’s home surveillance system.

Bodine was convicted last month of first-degree murder and faces a possible life sentence at a Dec. 17 hearing. Miller had testified against Bodine in exchange for the chance to plead guilty to a less serious charge in Evan’s death.

According to Miller’s testimony at Bodine’s trial, Bodine had been punishing Evan for not eating on May 19, 2017, when he took the screaming boy into the bathroom. She said he soon came out with her son’s wet and lifeless body in his arms. Miller said Bodine mixed up several bags of concrete and buried the boy’s body in it.

It would be four months before authorities found the body . By the time Evan’s body was chipped out of the concrete block, it was so badly decomposed that an autopsy could not determine how the boy died. He had Benadryl in his system, and Miller said she thinks Bodine sickened him in the days leading up to his death by force-feeding him large amounts of salt.

Evan’s father, Carlo Brewer, had been seeking custody of his son, and authorities had been alerted at least six times that Evan was being abused.

The boy’s father said after the hearing that he was pleased Miller took the plea deal because that means there won’t be another trial that the Brewer family will have to endure.

“It doesn’t make her any less of a monster than Bodine,” Carlo Brewer said, “because she’s just as guilty.”

The boy was the grandson of former Wichita Mayor Carl Brewer.