Bryan Kohberger, a 28-year-old doctoral student at Washington State University, made his first appearance in an Idaho court on January 5 after being extradited from Pennsylvania, where he was arrested on December 30.

A probable cause affidavit unsealed on Thursday revealed how DNA evidence, surveillance footage and cell phone records led law enforcement to Kohberger as the suspect in the November 13 slayings of Kaylee Goncalves, Madison Mogen, Xana Kernodle and Ethan Chapin.

Speaking for the first time since the affidavit was released, Goncalves’ sister Alivea Goncalves told NewsNation’s Brian Entin that it had felt like “the weight of the world” was lifted from the family’s shoulders when an arrest was made.

“I don’t think it really hit me until the affidavit was released and I was able to kind of read that and process that and then you not only have a name and a face, but you know, the beginnings of a case against him,” she said.

Goncalves said reading the details revealed in the affidavit was difficult.

“I think that that’s been the hardest part of this is to sit back and look at the totality of it. When my sister was FaceTiming me about a new egg bites recipe, he was planning his next visit to the home,” she said.

According to the affidavit, Kohberger’s cell phone was near the area of the King Road house in Moscow where the murders occurred at least 12 times in the months prior to November 13, and also that morning before the 911 call was made.

“It’s really difficult not to wish that you had done more, wish that you had known more,” Goncalves added. “We had no idea, she had no idea, I had no idea that true evil was genuinely watching them.”

However, Goncalves said the affidavit was “just the first step” and that “a lot more evidence will come out.”

She added: “I’m confident that Moscow Police Department, Idaho State Police and the FBI have the right person and I thank them from the very bottom of my heart.”

Kohberger’s public defender in Pennsylvania, Jason LaBar, said earlier in January that his client is “eager to be exonerated of these charges” and that he “should be presumed innocent until proven otherwise.” His attorney in Idaho, public defender Anne Taylor, didn’t respond to Newsweek’s request for comment.

Attorneys, law enforcement officers and others involved in the case have been placed under a"gag order," barring them from talking publicly about the case.

In the interview, Goncalves also defended one of the surviving roommates, who told investigators she saw a black-clad figure in the home on the night of the killings.

According to the affidavit, the roommate told investigators that she went back in her room and locked the door after seeing the man.

“She was probably really, really scared,” Goncalves said. “Until we have any more information, I think everyone should stop passing judgments because you don’t know what you would do in that situation.”