Idaho murder victim Ethan Chapin's sister shared the last text the University of Idaho freshman sent her just before he was killed in a home near campus on Nov. 13, 2022.Bryan Kohberger, 30, recently accepted a plea deal and confessed to killing Madison Mogen, 21, Kaylee Goncalves, 21, Xana Kernodle, 20, and Ethan Chapin, 20, in a 4 a.m. home invasion attack nearly two-and-a-half years ago.The night before the murders, Mazie Chapin the triplet sister of Ethan and Hunter Chapin had her sorority formal on Saturday evening and invited Ethan to be her date since she did not have one and his friends were going, Mazie says in a new Amazon Prime documentary series about the murders titled, "One Night in Idaho: The College Murders.""I dont usually invite anyone to formals, but some of Ethans friends were going, and he wasnt going," Maizie says in the docuseries. "So, I was like, OK, you can just be my date. It was super fun."READ BRYAN KOHBERGER'S SIGNED KILLER CONFESSIONThey left the formal around 9 p.m., and while some students went on to Ethan and Hunter's fraternity house, Mazie stayed behind."For some reason, I stayed and went to bed," she says in the docuseries. "Ethan kept texting me, Maizie, come hang out. I went to sleep, so I wasnt responding to any of them. Last one said, I love you, which was also weird because we dont say that to each other."IDAHO MURDERS TIMELINE: BRYAN KOHBERGER PLEA CAPS YEARSLONG QUEST FOR JUSTICEThe next morning, Ethan was found dead, along with Kernodle, his girlfriend; Goncalves; and Mogen. The four students had been stabbed to death in their rental home just steps from campus in the early morning hours of Nov. 13, a Sunday.Two-and-a-half years later, on July 1, Kohberger signed a confession as part of his plea deal to avoid the death penalty. He admitted to breaking into the off-campus house at 1122 King Road, in Moscow, Idaho, on Nov. 13, 2022, with the intent to commit murder. Then, with premeditation and malice aforethought, he stabbed Ethan Chapin, Kerndole, Mogen and Goncalves.BRYAN KOHBERGER EXPECTED TO OFFICIALLY PLEAD GUILTY: WHATS NEXTEthan's mother, Stacy Chapin, was in court on July 2, when Kohberger pleaded guilty to his crimes in person, a day after signing the confession."It was cold and calculated and weirdly, like an automated phone message," Stacy Chapin told "TODAY" of seeing Kohberger in court and hearing his plea. "I mean, it was just like you expected some, I don't know, remorse, emotion, something. And there was zero."FAMILY OF VICTIM IN BRYAN KOHBERGER CASE SAY THEY WERE SENT INTO 'PANIC MODE' AFTER PLEA DEALThe Goncalves family has been vocal in their disapproval of the plea deal, while the Chapin and Mogen families have supported the move. But despite their differing opinions, the families have expressed that Kohberger's deal with prosecutors caught them off guard."If I could physically do a handstand, I'd probably do one, because I am so ready," Jim Chapin, Ethan's father, told "TODAY." "I'm ready for my kids to move on. I'm ready for us to move on. I mean, it's been almost two-and-a-half years, and it's, just, it's over."Stacy Chapin said their first response in terms of the judicial process for Kohberger was "an eye for an eye," but after speaking with prosecutors, they agreed "this was a better deal.""He gets put away, and there's no appeal system to it," Stacy Chapin told the outlet. "And there were so many kids, including our own, that had been subpoenaed that no longer have this hanging over their heads."BRYAN KOHBERGER ACCEPTS PLEA DEAL IN IDAHO STUDENT MURDERS CASEKohbeger is expected to receive four consecutive terms of life in prison without parole, plus another 10 years.As part of the deal, he waived his right to appeal and the right to move for a future sentence reduction.Kohberger's trial would have begun in August.Fox News Digital's Michael Ruiz contributed to this report.