After Chris Watts killed his pregnant wife, he claimed the baby she was expecting was not his

Chris Watts was happy for his wife Shanann when she surprised him last May with the news that they were expecting a third child – a reaction she lovingly captured in a video that Shanann posted on her Facebook page.

But the triple murderer concealed this fact from another woman he met soon after – and when he actually confessed to his lover in August that his then-missing wife was pregnant, Watts claimed that Shanann had told him the baby was not his.

The details are contained in more than 2,000 pages of documents released by the Weld County, Colorado, prosecutor’s office after Watts pleaded guilty and was convicted this month of killing 34-year-old Shanann and her daughters Bella, 4, and Celeste, 3.

Shanann and the girls disappeared on August 13 after Shannan returned to the family home in Frederick, Colorado, following a brief business trip. They were reported missing by a family friend, after which Watts publicly pleaded for their safe return before being arrested and charged two days later.

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Shanann’s strangled body was later found in a shallow grave on an oil rig owned by Watts’ former employer; the bodies of the two strangled girls were found nearby in barrels of crude oil.

Shannan was 15 weeks pregnant at the time of her death.

To tell Watts the news of her pregnancy on May 29, Shanann put on a T-shirt with the words “Oops… we did it again” and wore it in the video recording she filmed when Watts arrived home that day. As Watts entered the house and walked toward her, the video shows him stopping mid-stride, starting to grin, then walking toward Shanann and saying, “We did it again.”

He is then seen on camera holding a pregnancy test. After leaning in and kissing Shanann, he says with a big grin, “I guess if you want it, it happens. Wow.”

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However, according to the documents, Watts told his lover, Nichol Kessinger, that he did not know about Shanann’s pregnancy until the day she disappeared, nearly 11 weeks later.

On the morning of Aug. 13 — when prosecutors say he killed Shanann and her daughters in order to make a “fresh start” with Kessinger, a co-worker with whom he had begun a physical relationship in July — Watts claimed he and his wife had been arguing, Kessinger told Watts police. According to Watts’ testimony, Shanann “became pretty mean” during the argument.

That was when, Watts told Kessinger, he first learned of Shanann’s pregnancy – adding that his wife told him “the child was not his,” Kessinger told investigators.

According to the documents, authorities dismissed Watts’ claim of alleged infidelity by his wife, who had made a steadfast effort to save the couple’s ailing marriage after nearly six years of crisis.

“Nichol said he pretended not to know Shanann was pregnant even though she was 15 weeks pregnant,” says the summary of an interview Kessinger gave to Colorado Bureau of Investigators agents on August 16.

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Kessinger learned of the pregnancy’s duration from media reports during the brief time authorities were searching for Watts’ missing family members.

“I thought, ‘If he could lie to me and hide something so big, what else was he lying about?'” Kessinger said in an interview with The Denver Post.

Watts was sentenced to three consecutive life sentences for the murders and two additional life sentences, as well as a 48-year prison sentence for wrongful termination of pregnancy in connection with the death of the unborn child, whom Shanann planned to name Niko Lee, according to her family.

Watts was also sentenced to 12 years in prison for three counts of tampering with a corpse.

As part of his guilty plea, he was spared the death penalty.