Ethan Chapin, Kaylee Goncalves, Xana Kernodle and Madison Mogen were found Sunday stabbed to death
There are new details surrounding the murders of four Idaho college students living off-campus. Investigators are trying to piece together just what happened the night they were killed in their beds as they hunt for a suspect.
A sister of one of the four college students found murdered at an off-campus house near the University of Idaho is revealing new clues.
The four students -- Ethan Chapin, 20; Kaylee Goncalves, 21; Xana Kernodle, 20; and Madison Mogen, 21 -- were found Sunday stabbed to death on the second and third floors of the home in Moscow, Idaho, according to authorities.
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"I was able to get a pretty good timeline on Kaylee and Maddy the night of, and from about 10:15 until shortly before 3 a.m.," said Kaylee's sister. Alivea Goncalves.
Alivea said she discovered at least six calls from her sister Kaylee's phone between 2:26 a.m. and 2:52 a.m. made to a boyfriend on November 13.
This new information adds more insight to the police timeline before the four friends were stabbed multiple times by a 'Rambo style' knife, likely while sleeping.
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Detectives are now saying these phone calls are part of their investigation. However, Kaylee's family is firmly standing behind that boyfriend.
"I know for an absolute fact that he's not a suspect. He's not suspicious. He is 100% innocent in this," Alivea said.
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Kaylee and Madison were last seen at this food truck moments before leaving with a ride-share driver. Police now said they do not believe that driver is involved.
Police are now also releasing a new map that is a part of the latest search area around the home and are asking for new surveillance video.
A TikTok showing Kaylee, Madison and Xana inside the home, just weeks before the brutal murders. The two surviving roommates are also in the video but their faces have been blurred because police have not identified them, but confirm the 911 call came in through one of their phones.
"I do truly believe that these girls probably feel so poorly. An absolute. Really traumatized," Alivea said. "I don't want them to feel that guilt, because I don't think that anything that they would have done could have changed this for the better."