Transcript for New details in case of missing Colorado mom
And we have chilling new details this evening in that case that made national headlines. The young mother last seen with her 1-year-old daughter on Thanksgiving day. Tonight, a newly released affidavit and what it reveals. ABC's kayna Whitworth is in Colorado. Reporter: After months of silence, tonight, newly released documents allege what prosecutors say was a horrific plot hatched by Patrick Frazee to murder Kelsey Berreth in cold blood with help from his mistress. Berreth last seen on this surveillance video thanks giving day. Frazee says that's the last T he saw her, too, when he picked up their daughter from their home. But prosecutors say a neighbor's security camera caught Frazee returning. They say he convinced her to wear a blindfold with the premise of guessing the scents of different candles, before bludgeoning her to death with a baseball bat. Kaylie was in the back room of Kelsey's condo when Kelsey was murders. Reporter: Frazee allegedly hitting Berreth so hard he knocked out some of her teeth. He then told his mistress Krystal Lee Kenney to go to the house, find the teeth, and clean up the gruesome murder scene. Krystal cleans up blood leaves behind some telltale evidence for our investigators to find. Reporter: Kenney confessing Berreth's body was put in a large black tote. And she and Frazee later watched it burn on his ranch. Berreth's remains have never been found. David, in their wrongful death suit, Kelsey's parents claim that Patrick's motive is that he wanted full custody of their daughter, Kaylie. The child remains with Berreth's
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