'Selfless' Utah Woman Is Killed, Boyfriend Is Suspect — and Sister Says She'd Just Made Plan to Leave Him

When Tyrese Cisneros last spoke to her older sister Lyberdee, Lyberdee said she had formulated a plan to leave a two-year relationship she described as abusive.

Two hours after that conversation, Lyberdee Cisneros had been shot dead at the age of 24.

"The last thing she had messaged me was a couple hours before she had passed away and word for word, she said, 'I'm going to see if I can rebuild a [legal] case on Jayden,'" Tyrese tells PEOPLE. "I want him put away [behind bars] so he can never hurt me or anyone else again. I had told her, 'I think you do whatever you need. Karma will get him, and a few hours later, she passed away.'"

"She never told me that until the night she died," she adds, about her plans to leave. "I think she told me because it was like a message from God that I had to fight for her. She would have wanted everybody to feel like they weren't the only one, and that she wanted to make a difference and to make sure that Jayden would never hurt anybody again."

According to a probable cause affidavit obtained by PEOPLE, Salt Lake City police responded to a call of a woman shot at the Downtown West Liberty Apartments at about 8 p.m. on Sept. 25.

Inside the apartment, officers found Lyberdee's 20-year-old boyfriend Jayden Fernelius, who according to police, had a 9mm handgun in his right front pocket.

Lyberdee, 24, was discovered lying face down on the floor. She had been shot.

Paramedics rushed her to the hospital where she died.

According to the affidavit, Fernelius had "significant amounts of what appears to be blood" on his clothes and blood on his hands when police spotted him.

The affidavit alleges Fernelius changed his story multiple times — including claiming that he'd heard a gunshot and then ran to the apartment to find Lyberdee dead.

He also claimed that Lyberdee attempted to hide the gun from him because she was worried he would "do something stupid," and when he tried to take it from her it fell to the floor. He allegedly claimed Lyberdee then picked it up and "shot into the floor and then shot herself in the neck, killing herself," the affidavit states.

The affidavit stated that contrary to Fernelius' account, "The victim was shot multiple times in a manner not consistent with self-inflicted gunshot wounds."

Tyrese says she and Lyberdee lived in various foster and group homes as children.

"She thought she could survive everything but Jayden," says her sister. "She had expressed to me that she was worried that Jayden would kill her one day. He would point the gun at her and he would just degrade her and call her really mean names. And call her fat, ugly, crazy, would judge my family."

All she ever wanted, says her sister, was a home to call her own.

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"She wanted to be reunited with her family and planned on me coming home this year to come be with all of us, because my mom wanted all of her kids in the same room," Tyrese says. "My mom won't get that ever again, and it makes me sad. That's all my sister wanted was to make sure everybody was okay. She was selfless and she put everybody first. "

Funeral services are scheduled for this week.

A GoFundMe page has been set up to help with funeral expenses.

Tyrese says her sister will be buried next to her beloved grandmother, who died in 2008.

"The night she had passed away, she texted my mom that she was very sad and that she wanted to be with my grandma," she says. "Everybody knows when they're going to pass away. I think that's why she gave me my message and that's why she gave me my mom's message. Now, we're on a mission to get my sister justice."

Fernelius is being held in Salt Lake County Metro Jail.

It is unclear if charges have been filed.

If you are experiencing domestic violence, call the National Domestic Violence Hotline at 1-800-799-7233, or go to thehotline.org. All calls are toll-free and confidential. The hotline is available 24/7 in more than 170 languages.