REXBURG, Idaho — The day after Idaho law enforcement and the FBI zeroed in on the house of the stepfather of two missing children, a neighbor of the children's mother is sharing what he witnessed right next door when the kids disappeared.

Rexburg Police, the Fremont County Sheriff's Office and the FBI have now searched the home of Chad Daybell and the townhouse of Lori Vallow.

They searched each location for completely different reasons. Chad Daybell's wife, Tammy, died in October and now authorities consider her death suspicious.

Lori's adopted son, 7-year-old Joshua "JJ" Vallow, and daughter, 17-year old Tylee Ryan, haven't been heard from since September.

Police think it's all connected.

The Daybell home in Salem is about 10 minutes from Lori's townhome in Rexburg.

One day before Thanksgiving, neighbors said police and the FBI raided Lori's townhouse, as well as her brother's townhouse in the same complex.

Damage is still visible on the door where neighbors said Lori's brother lived, from when law enforcement broke the front door down to get inside.

"It's crazy. Just baffling," said Seth Bernard, who lives right next door to Lori. He said he helped her move in a few weeks before school started in September.

He said Lori, her children, her brother and a friend had all driven up from Arizona. Seth said Lori told him she moved there to attend college.

Seth said he met Lori's daughter Tylee once, but never saw her again. He said Lori's adopted son, JJ, often played with his kids.

However, a couple weeks into the school year, he said he learned JJ was moving.

"What we were told... he was going to move with his grandmother, go visit," Seth explained.

Rexburg Police have since said that didn't happen. They said both JJ and Tylee haven't been seen or heard from since late September. That's when Seth said he stopped seeing JJ.

"Question is, where did they go?" Seth asked. "We have no idea. They just kind of took off and vanished."

Seth said Lori kept to herself. One day, a police officer showed up on Seth's doorstep, asking about Lori and her children. He said about a week later, two nights before Thanksgiving, he saw Lori and her brother packing up a truck. He figured they were going somewhere for the holiday.

"Next morning — Boom. They're gone," Seth said. That's when police and the FBI came crashing in.

Seth said Lori left behind her belongings, including JJ's toys, which now sit on the porch covered in snow.

Rexburg Police said they believe Lori and her new husband, Chad Daybell, have left the state and refuse to tell police the location of the children.

As police started to focus on Chad, it led them to his Salem home where his wife Tammy had passed away in October.

Fremont County Sheriff Len Humphries said originally, her death appeared to be from natural causes.

Now, they think it's suspicious.

On Friday, they executed a search warrant on the home in hopes of finding evidence and answers.

"Typically the family has not spoken with us in reference to this case, at all," Sheriff Humphries said.

The Daybell adult children, who live in the home and across the street, also declined to speak to Fox 13.

Sheriff Humphries hopes they'll get answers through the autopsy of Tammy's body, and the evidence they collected Friday.

Seth hopes police can find the kids.

"We knew these kids, they were playing with my kids," he said. "And all of a sudden, poof. They're gone."