The human remains found in doomsday author Chad Daybell's yard belong to his missing stepchildren, JJ Vallow and Tylee Ryan, their family says

• Human remains were found in the backyard of the doomsday novelist Chad Daybell in Idaho on Tuesday.
• His two stepchildren, JJ Vallow and Tylee Ryan, were last seen in September. Their mother, Lori Vallow, was arrested in February.
• Relatives of JJ and Tylee told reporters on Wednesday that the remains found in Daybell's yard belonged to the children.

Relatives of JJ Vallow and Tylee Ryan said that the two sets of human remains found on the property of the doomsday novelist Chad Daybell in Idaho were of the two children, The Associated Press reported on Wednesday.

JJ, 7, and his sister, Tylee, 17, were last seen in September.

Daybell was arrested on Tuesday on two counts of destruction or concealment of evidence and appeared in court on Wednesday. During the hearing, a state prosecutor said that the remains on the property were of two children and that one of the bodies was concealed in a "particularly egregious" way, East Idaho News reported. Daybell's bail was set at $1 million.

The children's mother, Lori Vallow, was arrested in February on child-abandonment charges after Idaho authorities said she refused to bring in her missing children. She and Daybell were vacationing in Hawaii when it was revealed that her children were missing.

"Throughout the investigation, detectives and investigators have recovered what's believed to be human remains that have not been identified at this time," Gary Hagen, the assistant police chief in Rexburg, Idaho, said on Tuesday. "I do want to add that Chad Daybell, who resides at that residence, has also been taken into custody for questioning in regards to that."

The police said on Tuesday that an autopsy would identify the remains. On Wednesday, Kay Woodcock, JJ's grandmother, told Justin Lum, a reporter for Fox 10 in Phoenix, Arizona, that the remains of her grandson were found on Daybell's property.

Lum said he later received a statement from the Vallow and Ryan families confirming that the other remains were of Tylee.

The police surrounded Daybell's property in rural Idaho on Tuesday to execute a search warrant. Investigators dug up land in the backyard and found the bodies of two children.

While investigators haven't confirmed the identities of the bodies, Rexburg Mayor Jerry Merrill said during an interview with ABC4 on Tuesday that it was a "sad day for the people who knew those kids."

"It is a sad day for Rexburg, you know, of course, to find out the news about the kids," Merrill said. "But on the other hand, it's a good day in the sense that it is good to try to bring some closure to the family and to this story."

The mystery surrounding the Vallow case has captured the attention of people around the world.

Vallow, who is connected to the doomsday group Preparing the People and has claimed to have supernatural powers, fled her home in Idaho in November to a vacation home in Hawaii when the police came to check on JJ.

Vallow and Daybell are at the center of several investigations involving the deaths of their previous spouses.

• Read more:
• The doomsday couple whose children haven't been seen since September is also at the center of several death investigations
• Doomsday couple Lori Vallow and Chad Daybell were found vacationing in Hawaii — but their kids are still nowhere to be found
• Doomsday author Chad Daybell claims his deceased wife helped him 'reconnect' with new wife, Lori Vallow
• Lori Vallow didn't meet the Thursday deadline to turn her kids over to the state. Their grandma believes the 'monster' will face consequences.