Many speculate that the children were deceased upon Shanann's arrival. Considering the fact that CW was not privy to her flight delay until much closer to the time she was to leave, wouldn't he have had more time to carry out an efficient plan of disposal? By this logic, he would have killed the girls, waited for her, and then did a rush job of getting ready for work, putting their bodies in the truck, disposing of their bodies, and then reporting to work. If he had so much extra time since her flight was delayed, why wouldn't he have already prepared the bodies and set the scene to play to his advantage? Perhaps, she arrived home, something started a conversation that quickly escalated, and then he killed her and then the kids.. Or it happened as he said and she killed them, then he killed her. Either way, it just seems off that they would have been dead for so long before her and he still couldn't set the scene right? The way he left everything goes more with the timeframe of 1:48 AM - 5:27 AM, not much time for three murders, clean up, and to report to work timely. Also, based on where her belongings were, it seems that she walked in, took off her shoes, set her suitcase by the stairs, walked to the kitchen and set her purse on the kitchen island, and walked upstairs with her phone (hence it being found in couch upstairs).. At that point.. Whatever happened, happened. Sometimes, things go terribly wrong. Doesn't mean a person was that way always. From the videos, one is not able to say either of them would be capable of this.