Revealed: Chris Watts' finalised plan to kill his family

It is still unclear what Chris Watts' motives for the murders were. Photo / Instagram

New documents from the Chris Watts murder investigation reveal shocking details about the final hours of his two young daughters, Bella and Celeste.

Watts had taken the girls to a birthday party on the afternoon of Sunday, August 12, and while Bella, 4, and Celeste, 3, played in the pool their father started texting co-worker Kodi Roberts.

At 5.06pm that evening, Watts set in motion his plan for disposing of his wife and daughters' bodies, as he texted Roberts that he would be making the drive out to one of the more distant oil fields that was managed by his company, Anadarko Petroleum Corporation, reports Daily Mail.

It is also where the bodies of Shanann, Bella and Celeste were discovered just days after they went missing.

Watts, per his own admission in interviews with law enforcement officials, then took his daughters home, gave them both showers, fed them pizza and got them each a snack before putting them to bed.

He noted that both girls were eager to see their mother, who was due to return home late that night.

Hours later, the girls and their mother Shannan were all murdered in the house, and their bodies disposed of at Cervi 6-29.

Chris Watts had selected the burial site for his daughters Bella and Celeste hours before their deaths while at a birthday party. Photo / Instagram

Shanann's father was one of the last people to see the girls, revealing he spoke to them on FaceTime on Sunday evening.

Frank Rzucek stated in an interview with law enforcement officials that he spoke with both Watts and Bella, who was eating cold pizza and candy.

He made no mention of seeing Celeste.

Watts claimed that he put the girls down before 8pm and that Bella woke up twice, running out to ask when her mom would be returning home.

The young girl's father and soon-to-be-murderer admitted to assuring her that she would see her mother in the morning.

A babysitter, who was the sister of the birthday boy whose party Watts and the girls attended that Sunday, also spoke with an agent with the Colorado Bureau of Investigation.

She said that on Saturday Watts had asked her to watch the children while he attended a Rockies game, though it was later revealed that he was actually on a date with his mistress, Nichol Kessinger.

She had babysat for the girls the previous evening, when Watts had claimed to be attending a Colorado Rockies game.

The babysitter said that while watching the girls Shannan called at 7.50pm to check on the children' while she was away and later posted a photo.

Christopher Watts sits in court for his sentencing hearing. Photo / AP

There was nothing remarkable that happened that night save for Watts returning home at 10.30pm, later than he had promised to be back at the house.

It was also her first time babysitting for the family, with the normal sitter who is a close friend of Shannon's not called in for reasons that are not stated in the reports.

Watts set up the babysitter the night before by texting her father, stating: "Do you think McKenna is available to watch the girls for a few hours tomorrow night? I won a raffle at work for a Rockies game. lt's with people I don't know from work, but I haven't been to a game in a while where the kids aren't involved and only last an inning lol."

The babysitter did have a different version of events as to what happened the following day though, saying that Watts left the party much earlier than he told authorities.

"[The babysitter] stated the following day, Sunday August 12, 2018, Chris, Celeste and Bella came to her home for a birthday party for her younger brother," reads the CBI report.

"Celeste and Bella are friends of her younger brother. [The babysitter] recalled Chris and his daughters left her home at about 3.30pm."

Watts' co-worker Roberts later told the an agent with the Colorado Bureau of Investigation that it was 'unusual' that Watts had texted him on a weekend, and stated that he did arrive to the site alone on Monday morning.

That day he did not seem to be out of sorts according to Roberts, but did make multiple trips to his car.

Unbeknownst to Roberts, he had just buried his wife in a shallow grave and dumped his daughters in an oil tank.

Watts' mistress, Nichol Kessinger claimed that his financial troubles were the main catalyst for the murders. Photo / Denver Post

After strangling his wife with his hands and smothering Bella and Celeste last August, Watts loaded their bodies into his truck.

He spent a normal day at work and frequently texted his girlfriend, even as police began investigating his family's disappearance.

He made calls to a real estate agent about selling the family home and told the girls' school that they would not enroll that fall as planned.

Within days, he was charged with killing his family.

The girls' bodies were found submerged in separate oil tanks on property owned by his employer. His wife's body was found in a shallow grave nearby.

As a prosecutor detailed the injuries at Monday's hearing, Shanann Watts' father leaned forward, gasping.

Christopher Watts' parents were permitted to speak at the hearing as the girls' grandparents. Cindy and Ronnie Watts urged their son to use his reprieve from a death sentence to make a full confession.

"We hope that he embraces that moment," the couple's attorney said.

Rourke doubts that moment will ever come.

"Those are the questions that will always haunt anyone who was involved in the investigation," he said.

"I don't think there is ever going to be a satisfactory answer for anyone."