(Newser) – The mother of two children missing since September failed to meet a court-ordered deadline to bring the kids to authorities in Idaho on Thursday. That clears the way for a judge to potentially hold Lori Vallow in contempt of court, a legal move that could allow prosecutors to seek to have her extradited from Hawaii to Idaho to face charges, the AP reports. Seven-year-old Joshua "JJ" Vallow and 17-year-old Tylee Ryan haven't been seen since late September, and police in Rexburg, Idaho, have said they "strongly believe that Joshua and Tylee's lives are in danger." "The only word coming to mind right now is 'monster,'" Kay Woodcock, JJ's grandmother, said during a press conference Thursday evening. "All this has just been very disheartening ... I'm a lot less optimistic at the moment."

Police have said Lori Vallow and new husband Chad Daybell, who were located in Hawaii this week, have lied about the children's whereabouts and even their very existence. The tangled case includes rumors of cult involvement and investigations into three separate deaths. Lori Vallow's estranged husband, Charles Vallow, was shot and killed in Phoenix in July by Lori's brother, Alex Cox. Cox, who claimed the shooting was in self-defense, died of unknown causes in December. In August, Lori Vallow moved her family to Idaho. In October, Chad Daybell's wife Tammy Daybell died of what her obituary said was natural causes. But when Chad Daybell married Lori Vallow just two weeks after Tammy's death, law enforcement became suspicious and ultimately had Tammy Daybell's remains exhumed. Test results have not been released.

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