Chris Watts, the Colorado father who admitted to killing his pregnant wife and two daughters, will be sentenced to life in prison without the possibility of parole later this month, prosecutors said. 

Watts, 33, pleaded guilty on all nine counts he was facing to avoid the death penalty. He was accused of strangling wife Shanann Watts, 34, and their daughters, Bella and Celeste, ages 4 and 3.

In the immediate aftermath of his Aug. 15 arrest, Watts struggled with depression in jail and was "despondent," a source told People magazine at the time.

After weeks of fighting it, Watts realized the evidence against him was "overwhelming," the same source told the magazine this week, and agreed to plead guilty. 

“Chris had to come to terms with reality,” the source reportedly said. “He didn’t like it at all, but he’s smart enough to know that his back was against the wall, and the best thing for him to do was to plead guilty.”

According to People, the source said, Watts was furious at having to enter the guilty plea. 

“His story didn’t work. He got angry," the source said. "... It took a little bit of time for him to come around, but he did.”

The three victims were reported missing on Aug. 13 by a family friend. Watts appeared on local TV pleading for their return on the day before he was arrested. He told police he had informed his wife he was leaving her. Investigators later discovered he had been having an affair with a coworker, authorities said. 

Watts will officially be sentenced on Nov. 19. 

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