The Florida teenager who murdered his classmate, a 13-year-old cheerleader, is "beyond saving," the victim's shattered mother testified Wednesday in court.

In a surprise move, Aiden Fucci, 16, pleaded guilty to one count of first-degree murder Feb. 6, the day jury selection was set to begin at his trial for stabbing Tristyn Bailey 114 times and leaving her body in a wooded area near a pond.   

"Your Honor, I plead with you, please consider everything he has done to our daughter and our family. Aiden Fucci made a heinous decision on May 9, 2021, and took the very life that I brought into this world," the slain teen's mom, Stacy Bailey, said through tears. "Please do not for one second think that he could be rehabilitated at any point. He is beyond saving."

AIDEN FUCCI TRIAL: FLORIDA TEEN CHARGED AS ADULT IN 13-YEAR-OLD TRISTYN BAILEY'S MURDER PLEADS GUILTY

Tristyn Bailey smiles next to a booking photo of her killer, Adrien Fucci

Aiden Fucci, right, stabbed Tristyn Bailey, 13, more than 100 times May 9, 2021, in Florida. (Bailey family/St. John County Sheriff's Office)

Bailey spoke on the second day of a sentencing hearing held before Judge R. Lee Smith in a 7th Judicial Circuit courtroom in St. Augustine. Tristyn's father and three of her four older siblings also tearfully addressed the judge, urging him to impose the maximum sentence.

Smith will decide whether to give Fucci, who is being tried as an adult, a minimum of 40 years to up to life in prison. His decision could come as early as Friday.

FLORIDA TEEN ACCUSED OF MURDERING 13-YEAR-OLD TRISTYN BAILEY: ‘DEMONS ARE GOING TO TAKE MY SOUL’

Fucci is not eligible for the death penalty because he committed the crime when he was 14.

Bailey described the frequent nightmares that now haunt her. "Visions flood my head how terrified she must have been," she told the court. "What went wrong in that moment of betrayal from someone she thought was her friend? Did she know it was coming? Did you wait for her back to be turned for the first strike of the knife?"

Stacy Bailey sobs as she reads from a statement.

Stacy Bailey gives a victim impact statement at Aiden Fucci's sentencing hearing for killing her 13-year-old daughter, Tristyn Bailey. (Fox News Digital)

State Attorney RJ Larizza previously revealed that Tristyn had 49 defensive wounds on her hands, arms and head, and that the tip of the hunting knife Fucci used broke off in her skull.  

MOTHER OF FLORIDA TEEN CHARGED IN STABBING DEATH OF TRISTYN BAILEY TAMPERED WITH EVIDENCE, POLICE SAY

"She fought, and our beautiful daughter suffered for so long as he took no mercy," Stacy said before staring directly at her child's killer, who was wearing a red prison-issue jumpsuit. "Aiden Fucci, you have destroyed me, you have destroyed my family."

Tristyn's sister, Alexis Bailey, was the first family member to address the court. She took the witness stand without speaking and methodically placed 114 turquoise stones into a jar, which took nearly two minutes.

Bailey family portrait

A portrait of the Bailey family. Tristyn Bailey, center, was brutally stabbed to death by classmate Aiden Fucci on May 9, 2021. (Bailey family)

"One for each of the 114 stab wounds that my sister had to endure," Alexis said. She glared at Fucci sitting at the defense table, as she peppered him with questions she knew he would not answer.

"Did she scream out for help or was she paralyzed with agony? Did she cry for my mother? Did she beg you to stop? Did you hear her lungs gargling with blood? Did you stay to watch her die?" Alexis asked. "Did you watch the life leave her eyes?"

Fucci's friends told investigators that he fantasized about violence and murder in the weeks before the slaying, drawing pictures of mutilated bodies. 

Tristyn Baily with her hair in pigtails poses next to a black horse.

Tristyn Bailey with a black horse. She was fatally stabbed by classmate Aiden Fucci on May 9, 2021, in Florida. (Bailey family)

Tristyn was a competitive cheerleader who attended Patriot Oaks Academy alongside Fucci. The night of her murder, she sneaked out of her house and was hanging out with Fucci and another classmate.

She was last seen alive on a surveillance camera walking alongside Fucci at 1:45 a.m. on a quiet street in the upscale suburb Durban Crossing outside Jacksonville. About two hours later, Fucci was seen emerging from a wooded area carrying his Nike sneakers in his arms.

The next morning, Mother's Day, her family realized she was not in her room and reported her missing. Police soon found her body near a pond in the neighborhood. 

A hunting knife with a broken tip used to murder Tristyn Bailey

The knife Aiden Fucci used to stab Tristyn Bailey 114 times in Florida. (7th Judicial Circuit State Attorney's Office)

"Our family broke that day and I don't recognize any of us anymore," Alexis said of the moment she learned of her baby sister's murder. 

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Tristyn's room remains the same two years later – her dirty laundry still untouched. 

"I can’t bear to change one thing, not even washing her clothes in the hamper as it would wash away the scent of her," Stacy said.