I recently moved to the Peterson's old neighborhood and so have taken more of an interest in this case than I had at the time. There are a few things that I've found particularly interesting.
First, they were in serious financial trouble. Everyone talks about how much money Kathleen made, but it was $145K/year and she had deferred 80% of her compensation (so she was bringing in only 20% of that the year before she died). She had banked on her stock and stock options, and if you recall, Nortel completely imploded in the days after 9/11, so her stock and options, which had been valued at $2 million at one time, had gone to nearly nothing. Also, $145K sounds like a nice, healthy salary, but when you consider that Michael was making almost nothing for a number of years, they had five kids (the two sons also in financial trouble -- Peterson wrote to his ex wife to ask her to take out a home equity loan to help them pay their credit card bills), three in college, and an enormous (10,0000 square feet) old house on four acres -- the maintenance of the house, the property, the taxes... no way can you do that on $145K (or, more accurately, 20% of $145K. Even if you factor in a little bit of residual benefits from the military to the two Ratliff girls, they were struggling. They had over $140K in credit card debt at the time of Kathleen's death. They were heading for total financial ruin, especially since it is almost certain that Kathleen would have soon lost her job (Nortel eventually went into bankruptcy).
Second, and for some reason almost totally forgotten, there was something decidedly "not right" with the oldest son (who knows about Todd, the younger one). Clayton tried to bomb Duke's administration building during his freshman year because he was angry that they were cracking down on drinking on campus. Yes, you read that right! He spent four years in prison. They found six bombs hidden in his parents' attic after the one he planted in the administration building was discovered. I found an interview with him online (I wish I could re-find it) and his explanation was that he was totally depressed because he had lived in Germany where he could go to clubs and bars and that he missed clubs and bars, and and he was staring in the face of spring break with no fake ID and the thought was just too awful to bear, so he decided to break in and steal the student-ID-making equipment and plant a bomb to serve as a distraction. I mean, he and his father (who was also interviewed for the article) seemed to think it was perfectly natural, when faced with the HORRORS of going on spring break with no fake ID, to plant a bomb as a diversion and steal a bunch of ID-making equipment.
The reason I even found that information is that I watched The Staircase, and in the episode where the blow poke is discovered by Clayton, there is a discussion with Peterson's lawyers of putting him on the stand, and they all decide it's for the best not to -- and they are coy about why it's so important not to put him on, mentioning ONLY his pending DUI.
Finally, Peterson ran for mayor, lied about his military honors, and was totally busted. And he, too, had a DUI.
I'm sure that's only scratching the surface of the weirdness that was going on in the family. For example, why was Todd at the scene so quickly after his father called 911? Why was Todd with a married woman that night?
ETA: I am on the neighborhood listserv, and someone recently posted photos of owls and said they were looking menacingly at her dogs. I hadn't heard the owl theory yet at that point, but now it makes me chuckle. Oh, and what could explain an owl feather? Um, maybe there was an owl in one of the trees near their pool where they were sitting and a feather dropped on her head???? Seems more likely than that it flew into the house and attacked her on the staircase???