Killer dad Chris Watts took photos of his young daughters and sent them to his wife who was away on a business trip, hours before murdering them all.
Watts, who is serving a life sentence in the US, killed his family (including his unborn son, Nico) so that he could start a new life with mistress Nichol Kessinger, reports news.com.au.
The Daily Mail reportedly obtained the photos under an Open Records Request
There are also a number of photos taken by Watts' mistress Nichol Kessinger that the killer hid away in a secret calculator app on his phone.
The pics of Bella and Celeste show the two eating a snack and hanging out with the family dog in what would be the final hours of their lives. Watts sent the photos to Shanann who was away at a conference in Arizona.
Returning from the conference later that night, Shanann was murdered by her husband, who buried her and their unborn baby boy in a shallow grave on a remote oilfield that was owned by his employer at the time Anadarko.
Watts then smothered his two daughters and put their bodies in an oil tank.
It comes as the house where the brutal murders took place is up for sale.
The auction of the Watts family's $US485,000 ($A690,000) home was pushed to July back in April, just days before it was set to be offloaded to the highest bidder.
That move comes after Watts finally revealed to investigators just how he murdered his wife inside the home, before dragging her body down the stairs and loading her into his truck with daughters Bella and Celeste.
Shanann's family had been seen removing her possessions from home shortly after her death and then again once the trial was concluded.
Watts accepted a plea deal of life in prison after confessing to the murders. He is now jailed in Wisconsin.
It was just a few hours after he buried the body of his wife and dumped his daughters in oil tanks that Watts' alibi began to fall apart.
That was due in large part to the surveillance footage his neighbour had of Watts on the morning of the murders, which very clearly showed him back his truck up to his garage, load up the vehicle and drive off.
Watts had told police and his wife Shanann's friends and family that she and daughters Bella and Celeste had run off that day while he was at work, but footage proved that was not the case.
In fact, the footage did not capture anyone leaving the house that day but Watts.