Kimberley Mills, the mother of a 10-year-old boy charged with torturing her 10-year-old son to death, was sentenced to life in prison Wednesday, and will now be a key witness in the death penalty case against her former boyfriend, Andre D. Walker.

Kimberley Mills pleaded no contest to being a principal to first-degree murder and three counts of aggravated child abuse, which included her son Amir, who was 8 at the time of the crime.

 “Miss Mills has asked me to let the court know she loves her sons very, very much,” Assistant Public Defeder Morris Carranza told Circuit Judge Cary Rada. “The most important reason is to prevent her son, Amir, from being retraumatized by testifying against her.”

There was “a number of reasons” she pleaded no contest, Carranza told Lake & Sumter Style on Thursday.

Perhaps the most practical, unspoken explanation is that it will prevent her from being strapped to a gurney and getting a lethal injection.

The boys’ father, Keniel Williams, who agreed with prosecutors in accepting the plea, was so devastated by the crime that he had to leave the courtroom briefly while trying to give an impact statement, said Assistant State Attorney Ken Nunnelly.

“Our focus has always been justice for this child and accountability for those responsible,” says State Attorney Bill Gladson in a press release.

“Mills’ plea, which includes truthful testimony against her co-defendant, strengthens our ability to pursue that goal and ensures the full story is brought before the court. In doing so, Mills will spend the rest of her life incarcerated. I have no doubt she will think of Xavier every waking day and regret the pain and suffering she made him endure while she repeatedly endures her own.”

The couple drove to Advent Health Waterman Hospital on Feb. 22, and he rushed into the emergency room shouting, “We need help. Hurry up!” according to police records.

Mills, who was a registered nurse, was performing CPR on Xavier in the back seat. An ER nurse noticed bruising and asked Mills what happened.

“I don’t know, Xavier started vomiting and then he was like this,” she said, according to police records.

She refused to tell police what happened.

He remained in critical condition until he died.

The 10-year-old was duct-taped to a ladder and had a 10-pound dumbbell dropped on his abdomen, according to the probable cause affidavit. Amir told police he was whipped with a metal rod and hit with a flashlight.

A police officer noticed severe bruising and several burn marks on Xavier’s stomach and right bicep. The doctor found an arterial bleed in his abdomen and several bruises in various stages of healing. Some of the bruises were on his face.

Amir said the adults sometimes pummeled them with boxing gloves.

There was not a bed in Xavier’s room, just a mattress without sheets leaning against the wall.

The younger boy’s room did include a bed.

Police said Mills covered up the boys’ injuries by having them wear long-sleeved shirts and telling them not to tell anyone.

“The death of Xavier is one of the most heartbreaking crimes our community has ever faced,” says Tavares Police Chief Sarah Coursey.

She said her agency will continue fighting for justice in the case.

Walker’s case has not been scheduled for trial. He is represented by private attorney Javier Chavez out of Orlando.