Last Celebration! Chris Watts Finalized Murder Plan At Kids' Birthday Party

Chris Watts hatched his evil murder plan at a kids' birthday party, it has been revealed.

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

It has emerged that their father took them to a 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.

In the texts he hatched his evil murder plans to dispose of his wife, Shanann, and their two daughters bodies also.

Watts texted Roberts that he would be making the drive out to one of the more distant oil fields run by his company, Anadarko Petroleum Corporation.

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

After finalizing his plan, Watts told authorities that he gave the girls a shower, fed them pizza and a snack, before putting them to bed.

Chillingly, his daughter Bella, got up twice asking when her mother would be home and Chris told her that she would see Shanann in the morning.

However, he murdered both his daughters as they lay in bed before they ever saw their mom again.

Watts agreed to a plea deal in the case and was sentenced to life in prison after he confessed to the killings.

Investigators are still trying to establish what the motive was for him killing both his daughters and his pregnant wife after she returned home from a business trip.