PHOENIX (AP) — The adult niece of an Idaho woman whose two children have been missing for five months is cooperating in the FBI’s investigation into the disappearance, undergoing three interviews with agents and surrendering her computer, the niece’s lawyers have said.

Melani Pawlowski was accused by her ex-husband of knowing the whereabouts of Lori Vallow’s two children yet failing to cooperate with authorities.

Joshua “JJ” Vallow, 7, and 17-year-old Tylee Ryan were reported missing in September. An investigation into their disappearance has stretched across several states to Hawaii, where their mother is jailed.

Garrett Smith, one of Pawlowski’s attorneys, said the niece hasn’t seen the children.

“She doesn’t know where they are,” he said last week. “No one has told her where they are.”

Last fall, Pawlowski moved from Arizona to Rexburg, Idaho, to live closer to Lori Vallow. Her apartment next door to her aunt was searched by police in the investigation into the children’s disappearance. Smith said Pawlowski remains fond of her aunt and is reserving judgment on her.

The claim that a relative might hold the key to finding the children is the latest turn in a sprawling tale that has unfolded in several states, involves claims that Lori Vallow and others were influenced by doomsday religious beliefs and includes investigations into the deaths of three people.

Lori Vallow’s estranged husband, Charles Vallow, was fatally shot in July in the Phoenix area by Lori Vallow’s brother, Alex Cox. Then Cox, who claimed the shooting was in self-defense, died of unknown causes in December. Police are investigating Cox’s death.

Lori Vallow moved last summer from suburban Phoenix to Rexburg and later married Chad Daybell, an author of religious-themed fiction books about prophecies and the end of the world.

Daybell’s previous wife, Tammy Daybell, died in mid-October of what her obituary said was natural causes. Vallow’s marriage to Chad Daybell two weeks after the death raised suspicions among law enforcement and led to the exhumation of Tammy Daybell’s remains.

Vallow told police that JJ was in Arizona with a friend, who later said the boy hadn’t been to her house for months.

Police say Vallow has refused to provide any information on her children’s whereabouts. She remains jailed in Hawaii on child abandonment charges from Idaho. Chad Daybell hasn’t been charged with a crime.

The allegation that Melani Pawloski knows the children’s whereabouts surfaced in a child custody filing made by her ex-husband, Brandon Boudreaux.

Boudreaux expressed concern that his children were at risk in his ex-wife’s care and said she had regularly spent time with their four children at Vallow’s home.

“Mother’s knowledge of the whereabouts of her aunt’s two missing children and her unwillingness to cooperate with law enforcement in finding those children, is daunting to the father,” said Bradley Crider, Boudreaux’s attorney.

Crider didn’t return phone calls and an email seeking elaboration on the claim that Pawlowski knows the children’s whereabouts. Efforts to reach Boudreaux for comment through email and messages left by phone and social media were unsuccessful.

In yet another surprising turn, someone parked in a Jeep outside Boudreaux’s home in suburban Phoenix fired a rifle shot at him in early October, missing Boudreaux’s head by inches and shattering a window on his Tesla, before fleeing the scene, according to police records and Boudreaux’s court filings.

Boudreaux recognized the Jeep as the vehicle that Tylee Ryan regularly drove. Police later seized a Jeep in Rexburg that had been registered to Charles Vallow, who was killed nearly three months prior to the shooting outside Boudreaux’s home, according to police records.

While Crider alleged Melani Pawlowski was under investigation in the shooting, police say she hasn’t been identified as a suspect.

“We are unable to substantiate the claims made about Mrs. Pawlowski in the child custody court filings submitted by Mr. Boudreaux,” the Gilbert Police Department said.