Kaylee Goncalves’s sister delivered a blistering takedown to Bryan Kohberger on Wednesday as he was sentenced to life in prison — savaging the pervert killer as a “sociopath” and ordering him to “sit up straight” — even as he refused to speak up and explain why he butchered Goncalves and the three other Idaho coeds in their home in 2022. 

“You want the truth? Here’s the one you’ll hate the most: If you hadn’t attacked them in their sleep, in the middle of the night like a pedophile, Kaylee would have kicked your f–king ass,” Alivea Goncalves told the convicted murderer, as the courtroom erupted in applause.

At one point during her victim impact statement, Kohberger appeared to take sick pleasure in the verbal lashing — flashing a scummy smile at Alivea.

Other than that brief moment, he wore a blank expression on his face through the entire proceeding.

She added: “Disappointments like you thrive on pain, on fear, and on the illusion of power. And I won’t feed your beast.

“Instead, I will call you what you are: Sociopath. Psychopath. Murderer,” she said, adding, “Sit up straight when I talk to you.”

But when it came time for the failed PhD criminology student to speak — and potentially answer the question every family member was asking, why he did it — Kohberger stayed silent.

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When a judge asked him if he had any comments, Kohberger stood and said, “I respectfully decline.”

His exact motive for targeting that house on that night could remain a mystery forever. In a press conference after the hearing, investigators revealed they found no social media posts or any other evidence connecting Kohberger to his victims.

Goncalves delivered some of the most memorable lines of the four-hour sentencing hearing, but family members for victims Madison Mogen and Xana Kernodle also tore into Kohberger — explaining how the murders had destroyed their lives, and how they would be moving on while he rots in prison.

The family of Ethan Chapin, 20, was not present — saying the plea deal that condemned Kohberger to spend the rest of his life in prison in exchange for dodging a firing squad — had given them closure enough. 

Goncalves also took aim at how Kohberger, who appeared to fancy himself a criminal mastermind, made so many obvious errors during his bloody crime.

“Did you truly think your Amazon purchase was untraceable because you used a gift card?” she said, referring to how he bought the murder weapon online. “Please describe the anxiety you felt when you heard the [police] pull up to your family home on Dec. 30, 2022.”

Kohberger — shackled at the waist and wearing an orange prisoner’s jumpsuit — appeared to shift uncomfortably in his seat as she pushed the onslaught, swallowing and blinking as Goncalves spoke in some of the first movements he made since the hearing began.

“If you were really smart, do you think you’d be here right now? What’s it like needing this much attention just to feel real? You’re terrified of being ordinary, aren’t you? Do you feel anything at all? Or are you exactly what you always feared — nothing?” Goncalves said.

“You worked so hard to seem dangerous, but real control doesn’t need proving,” she added, lambasting Kohberger’s arrogance for believing he was “elite” and “special” for years because of an online IQ test he took as an early teen.

“The truth is you’re as dumb as they come. Slow, sloppy, weak, dirty,” Goncalves said, while Kohberger looked murderously on.

Goncalves’ fiery speech was characteristic of her family, who have been vocal about punishing Kaylee’s killer to the fullest extent of the law since the 21-year-old was found butchered alongside her roommates on Nov. 13, 2022.

Father Steve Goncalves also tore into Kohberger Wednesday, calling him a “joke” during his victim impact statement.

“You’re a joke, a complete joke,” he said, while ridiculing the lazy trail of evidence Kohberger left behind at the scene of his gruesome quadruple University of Idaho murder.

“You were that foolish, that careless, that stupid,” Goncalves added, pointing out how police told him Kohberger’s DNA was found “within minutes” along with footage of his car arriving and leaving the scene of the crime.

“Today we are here to prove to the world that you picked the wrong families,” he said. “Our actions have united everyone in their disgust for you.”

“Today you have no name,” he concluded. “Nobody cares about you. You’re not worth the time, the effort to be remembered. In time you’ll be nothing but two initials forgotten to the wind.”

Victim Xana Kernodle’s father also shockingly revealed that he was near the University of Idaho the night of the murders, and nearly spent it sleeping on his daughter’s couch after she told him she was feeling sick.

“I was seven miles away when it happened,” Jeff Kernodle told the courtroom. “And I almost went over to Xana’s to stay, and I would have been sitting right there on that couch. And you would have had to deal with me. So they would have had a chance.”

“I regret that. I regret not going. But the reason why I didn’t was Xana said ‘Don’t be drinking and driving.’ She would have been mad at me. But I really wish I would have drunk and drove. Because they would have had a chance, all four of them.”

Maddy Mogen’s father also delivered a heart wrenching statement, fighting back tears as he told how his “only child” was a shining light that kept him alive through periods of addiction and darkness in his life.

“She encouraged me not just to do my best, but to live on,” Ben Mogen said. “When I wasn’t wanting to live anymore, she was what would keep me from not caring anymore. Knowing that she was out there, and knowing that she was such a beautiful person, kept me alive a lot of rough moments.”

“She was the only great thing I ever really did, and the only thing I was ever proud of,” he added. “I thought we would have the rest of our lives together.”

Kohberger’s decision not to speak means the world may never hear from him why he did it – but Judge Steven Hippler told the court people should try not to dwell on that, as it was unlikely anything somebody as foul as he is could ever really be believed.

Hippler then sentenced Kohberger to life without the possibility of parole or appeal.