An Idaho nurse is expected to be charged in connection with the disappearance of Kelsey Berreth, a Colorado mother who was last seen on Thanksgiving Day and who authorities say was murdered by her fiancé.

Krystal Lee, 32, is scheduled to appear in Teller County court Friday morning on one count of tampering with physical evidence, FOX31 reported. Lee, a nurse in Twin Falls, Idaho, is accused of helping Berreth’s fiancé, Patrick Frazee, in disposing of evidence linked to Berreth's disappearance.

KELSEY BERRETH’S FIANCÉ HIT WITH 5 FELONY COUNTS, INCLUDING MURDER

Berreth was last seen on surveillance video entering a Safeway grocery store in Woodland Park with her 1-year-old daughter, Kaylee, who she shared with Frazee. Her cellphone then pinged from Gooding, Idaho -- three days after she was last seen alive.

Joe and Patty Rockstahl previously told KMVT they contacted the FBI after one of their employees told them in October that her best friend said, “a man had asked her to kill the mother of his child.” The couple, who own Rockstahl Law Offices, connected that grim information to Berreth’s case.

Frazee was arrested in late December and charged with first-degree murder, first-degree felony murder and three counts of solicitation to commit first-degree murder after authorities found enough evidence to connect him to his fiancee’s disappearance.

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Berreth’s body has not been found and police and prosecutors haven’t said how she was killed or why. They haven't discussed what evidence they've obtained to charge Frazee.

“All the facts in this case are under seal so I cannot talk to you about any potential motive,” Teller County District Attorney Dan May said.

Fox News' Robert Gearty contributed to this report.