Killer dad Chris Watts had a change in his behavior weeks before killing his pregnant wife and children, according to his coworker.

Watts was working as an oil field operator in 2018 at Anadarko Petroleum Corporation in Frederick, Colorado. He was living at the time with his pregnant wife, Shanann Watts, and their two daughters.

A contractor who worked with Watts for several years told People that "things and the killer dad had "changed" weeks before killing his family, and it was unclear what had caused the sudden change. According to Brian Spence, he saw Watts becoming increasingly unhappy with his life.

"He went from being a friendly guy to being withdrawn and angry... I saw him lose his temper over little workplace annoyances.. He had an irritable side with the contractors. He could be combative," Spence told the outlet.

He also said that Watts was no longer in a hurry to go home every day after work. Spence noted that Watts had a lot more happy hours with the contractors, getting beers with them after work. However, he said the killer dad was "always one of the last ones to leave."

"We're all family men and had to get home to our kids, so we'd drink from 6 to 7 and then go. He'd want to stay past 8 if anyone was willing to stay," Spence noted. 

However, despite the change in Watt's behavior, Spence said he did not suspect that Watts would eventually kill his family since he was "not the first unhappy guy in the history of the world, and most of them don't kill their wives."

Spence added that he knew Chris Watts was having an affair with a co-worker. He said the killer dad did not talk about his affair, but he was always saying that "this or that chick" wanted to have sex with him.

"I didn't know it was actually happening. I thought it was just talk... He was obviously in pain. If I had any idea, I would've pulled him aside and said something. But he hid it. No one knew," Spence noted.

READ NEXT: Killer Dad Chris Watts Blames Mistress Nichol Kessinger for the Murder of His 2 Young Daughters, Says She Smothered Them

Chris Watts Sending Texts to Mistress Nichol Kessinger After Killing His Family

Chris Watts reportedly sent text messages to his mistress Nichol Kessinger after he killed his wife and children. According to U.K. Mirror, Watts had denied harming his family when Kessinger asked him what he did to his family.

Kessinger said she was stressed out at the time and texted Watts one last time, saying that if he did anything bad, he would be ruining his life and her life. She noted that the killer dad responded that he did not hurt his family.

Kessinger said it was the last text she sent to Watts, and "I never said another word to him after that." Kessinger was seeing Watts even though he was married, saying in a police interview that they had discussed his "current relationship" on several occasions, but it was "never hostile." 

Kessinger noted that Watts told her he had a "disagreement" with his wife on the day of the killings. She noted that she had tried to convince Watts to go and look for his family when they were reported missing.

Nichol Kessinger said that Chris Watts did not seem concerned as he should be and was more concerned with their relationship.

Killer Dad Chris Watts Killing His Family

According to Biography, Chris Watts told Shanann Watts about his affair and said their marriage will not last.  She then replied that Watts will not be seeing their children again. Watts then strangled her to death on August 13, 2018.

Their four-year-old daughter Bella came in and asked what was wrong. Watts then wrapped his dead wife in a blanket and carried her to his truck. Watts then seated Bella and his other daughter, Celeste, 3, in the backseat, just above their mom's dead body.

The killer dad then drove to an oil work site some 40 miles from his home. Watts eventually admitted that he had not planned to kill his two daughters but smothered them there and placed their bodies inside an oil tank. He also confessed that he had buried his wife's body in the nearby ground.

Chris Watts pleaded guilty to the crimes in November 2018. He is now serving a total of five life sentences in prison without the possibility of parole at the Dodge Correctional Institution in Wisconsin.

READ MORE: Chris Watts Tried to Poison Shanann Watts With Oxycodone Weeks Before Her Murder, Pen Pal Says

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Written by: Mary Webber

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