SAVANNAH, Tenn. (AP) — The brother of a man serving life in prison for kidnapping, raping and killing Tennessee nursing student Holly Bobo pleaded guilty Monday in exchange for a 35-year sentence.

John Dylan Adams entered an Alford plea, which means that he maintains his innocence, but acknowledges that prosecutors have enough evidence to convict him of especially aggravated kidnapping and facilitating first-degree murder. Judge C. Creed McGinley accepted the agreement, sparing the victim's family from having to "listen to the horrible details" at another trial.

Bobo's mother, Karen, said she was prepared to endure it again, but is satisfied with Adams' guilty plea in the most exhaustive and expensive case in the history of the Tennessee Bureau of Investigation.

"For the sake of our family and just letting one more chapter be behind us, we decided we would go with this," she said.

Bobo was 20 when she vanished from their home in rural Parsons, Tennessee, in April 2011, prompting a massive search of woods, fields and farms in west Tennessee. Her remains weren't found until more than three years later, in September 2014, by two ginseng hunters in woods not far from their home, about 100 miles (160 kilometers) southwest of Nashville.

John Dylan Adams is the younger brother of Zachary Adams, who is seeking a new trial after being convicted and sentenced to life without parole plus 50 years in a last-minute deal in September that avoided the possibility of a death sentence.

A TBI agent testified at Zachary Adams' trial that the agency made a mistake when it did not pursue leads only days after Bobo went missing that pointed to four men who lived in a dark underworld of crime and drug use: the Adams brothers and their friends Jason Autry and Shayne Austin.

Investigators were unable to recover any DNA pointing to the four suspects, who ultimately would be accused based on witness statements.

Autry, also charged with Bobo's kidnapping, rape and murder, testified in expectations of getting a lenient sentence and is on a list of witnesses who have been offered immunity. He said the elder Adams told him in graphic detail how he, his brother John and Austin raped Bobo. Autry also testified that he served as a lookout while Zachary Adams shot Bobo under a bridge spanning the Tennessee River. Austin committed suicide in Florida in February 2015.

A fellow jail inmate, Shawn Cooper, testified that Zachary Adams told him he was involved in the "Holly Bobo murder case" and wanted him to deliver a message to his younger brother: Stay quiet, or he would "put him in a hole beside her." At the time, Cooper was about to be transferred to the same jail where John Dylan Adams was being held.

Autry, meanwhile, testified that Zachary Adams asked him to kill his younger brother to silence him.

Prosecutors have not publicly revealed the details of John Dylan Adams' involvement, but Shelby County Assistant District Attorney Paul Hagerman did say Monday that he had less involvement than his older brother.

No hearing has been set to resolve Autry's charges, but his lawyer has told the judge that a trial does not need to be set, indicating that he has reached a deal with prosecutors.