WHAT WAS CHRIS WATTS' MOTIVATION TO MURDER HIS WIFE & KIDS? WATCH EXPERT WEIGH IN

Why would Chris Watts murder his wife and two daughters? Dr. Oz’s senior correspondent Mara Schiavocampo sheds light on his “motivation” for the crime.

“It's completely unfathomable. He had fallen in love with another woman and he wanted to start a new life with her,” the investigative journalist told Dr. Oz.

“Just six weeks before these murders. Think about how short of a time frame that is. Six weeks prior, he started an affair with a coworker, a woman named Nichol Kessinger. Now, she says that he did not tell her that his wife was pregnant at that time, and he also said he was in the midst of a separation.

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“Now, even though she had nothing to do with these murders, the backlash against the other woman was so fierce when the details of this came out, that she is now in the witness protection program, but this affair was his motivation for this terrible, unthinkable crime,” she concluded.

On August 13, 2018, Chris Watts murdered his wife Shanann — who was pregnant at the time — then drove his two daughters, Bella, 4 and Celeste, 3, with their dead mother's body in the family truck to a remote oil field where he worked and smothered the two children before tossing their bodies into an oil tank.

Watts and Kessinger met when they were both working for Anadarko Petroleum in June 2018 and started having an affair in early July of the same year.

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When they first started seeing each other, Watts was not upfront with Kessinger about his current relationship status. He “did not have a wedding ring on his finger” and “he never mentioned he was in a relationship and did not initially mention his children,” documents obtained by OK! revealed.

The documents also disturbingly revealed that on the day Watts killed his family, the former oil field worker “FaceTimed” with Kessinger and was “laying on a mattress that did not have sheets on it.” Watts “said he was cleaning his home and trying to keep busy to keep his mind off things,” the files read. “Nichol inquired why the bed in the video call did not have sheets on it and Chris told her he had washed the sheets. Chris was quiet during this video call and did not say much. Nichol said Chris was fixated on her and was staring at her during the video call.” 

Kessinger was questioned by the police three days after the incident. “It’s not fair. It wasn’t fair to me in the first place, it wasn’t fair to her in the first place, it wasn’t fair to any of us in the first place, you know,” she told investigators at the time about how Watts deceived her.

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Kessinger admitted during the interrogation that she knew her name would be “slandered” for “probably a while,” adding that she didn’t know “how long it’s gonna take to heal.”

OK! previously reported that Kessinger filed a petition in October to have her name changed so she can leave the whole ordeal in the past and not be known as the murderer's mistress.