The Utah teacher accused of fatally shooting her ex-husband’s girlfriend in front of her own twin daughters allegedly snuck into the apartment where she’d commit murder after luring her ex outside with a ruse.
A Salt Lake City police spokesperson tells PEOPLE that before the Nov. 25 shooting, Chelsea Watrous Cook, 32, had arranged to give ex Travis Cook cough medicine for the couple’s children in the parking lot outside his apartment building.
But according to a probable cause affidavit obtained by local station KUTV and the Salt Lake Tribune, the suspect was instead seen on surveillance camera sending a text message in the apartment building’s hallway.
“Shortly thereafter, Mr. Cook exits his apartment and once he is out of sight [Chelsea Cook] enters the apartment without knocking,” according to the affidavit, KUTV reports.
According to the affidavit, Travis Cook told investigators that when he reentered the apartment, he found Cook inside and asked her to leave but she refused. She then locked herself in the bathroom for 15 seconds before coming out to get her coat, after which she allegedly pulled out a handgun and fired multiple times upon her husband’s girlfriend, 26-year-old Lisa Vilate Williams, who later died from her injuries.
Cook — who according to her Facebook page worked as a health and yoga instructor at Skyridge High School in Lehi — is charged with aggravated murder, burglary and violence in the presence of children.
At the time she was fatally shot, Williams was decorating a Christmas tree with the 3-year-old twins her boyfriend and Cook shared.
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After allegedly shooting Williams, Cook sat down in a chair with her two children while Travis Cook called 911. She then got up and reached for her coat again, before Travis Cook pinned her to the wall and told his children to go to their bedroom until authorities arrived.
Following her daughter’s death, Williams’s mother Tawny Williams shared a heartbreaking post on Facebook.
“My beautiful Lisa, she was murdered while decorating a Christmas tree with homemade ornaments she was making with the kids (3 year old twins),” Tawny wrote. “She was so kind, sweet, generous, loving, and brought joy and excitement to every aspect of life.”
A GoFundMe page was launched in the hopes of helping her family cover her funeral costs.
Williams and Travis Cook had been dating for six months before her death. Williams’s family told the Associated Press Cook had allegedly been harassing their loved one on the phone, online and in person.
“I worried for her safety every day,” Tawny Williams said, the AP reports.
Cook also faces domestic violence charges in a Herriman justice court following an incident that took place last month, according to Deseret News. Cook allegedly caused minor injuries to an unidentified man in her apartment. She has previously pleaded not guilty in that case.
Cook has not yet entered a plea to the new charges and remains behind bars in Salt Lake County Jail on a $1,000,000 bond, according to jail records. Her attorney could not be reached for comment.