REXBURG, Idaho (KIFI/KIDK) - New details are being revealed about the growing mystery behind the two Rexburg children who disappeared more than three months ago.
Joshua "JJ" Vallow's grandparents Larry and Kay Woodcock are now issuing a $20,000 dollar reward for anyone who can bring them home safely.
Our Kaitlin Miklos breaks down this case in a timeline of events leading up to the disappearance of several people connected to this mystery.
The search for 7-year-old JJ Vallow and 17-year-old Tylee Ryan is growing more desperate as the grandparents left their home and are now in Rexburg searching for answers. The kids are gone, their mom is one the run and several family members are dead.
"Someone out there, someone, you can't tell me someone doesn't know something about these children," Larry said Tuesday during a press conference.
"Call us. Do it. We'll be there as quick as we can. We'll get authorities out there to pick you up," the grandparents said.
Lori Vallow (Lori Daybell), now on the run, was married to Kay's brother, Charlie, who was filing for divorce and custody of the kids.
Court documents show she threatened to kill him. Five months later, her brother shot and killed him in Arizona in July.
Shortly after Charlie is killed, Lori moves from texas to Rexburg right before school starts.
"After Charles was murdered July 11, we've had three very short contacts with JJ," Kay said. The final time in August was only 36 seconds.
They describe why they believe JJ was not on that call alone.
"Yes. There was someone else there. It's like someone was holding something up and he looked at it and said, "Gotta go, bye." It was that fast."
By Sept.23, that's the last time anyone would see the two kids.
Just weeks later in October, Chad Daybell's wife Tammy is found dead in their Rexburg home just 10 minutes away from Lori's townhouse.
Two weeks later, Daybell becomes Vallow's fifth husband.
Growing suspicion leads to authorities performing a welfare check at Lori's townhouse where she lied to police that JJ was staying with family in Arizona. That same night, neighbors tell us they saw Lori and Chad packing up and moving out.
Then the day before Thanksgiving, authorities are seen raiding that now-empty home. Days later, now into December, police exhume Tammy's body where her cause of death is still under investigation.
The very next day Lori's brother Alex Cox, who shot her former husband, dies of suspicious causes. His death also now under investigation.
Then on Jan. 3, the FBI is seen hauling more than 40-pieces of evidence from Chad's former home. So far, they're staying tight-lipped about their findings.
The Daybells, now on the run, are refusing to cooperate with police.
Authorities don't believe the kids are with the parents but say Lori knows where they are and what happened to them.
For now, the search for the two kids is turning-up few leads.
"My life's too short. All of our lives are too short. We're not promised tomorrow. All I want before I go is just to see those children," Larry said.
Right now, the family says they have hope the kids are still alive.
You can watch Tuesday's press conference below.