Please tell me you aren't thinking about a dog eating KB's remains.
I am thinking that part of PF being so sure is because he was/is positive that the body would not be found.
He learned several things from CW case.
- that you can not let people get wind of the disappearance too soon. Hence, Thanksgiving date and false texts postponing the time the case is opened by the police.
- that you can not give any interviews nor polygraph. Better, lawyer up.
- that you can not allow the body to be found. Basically, there is no good hiding place. LE will either trace your car route, or cadaver dogs will be alerted, or somehow they will track you.
So I believe that the body was dismembered and probably, taken out of the house in pieces. 15 min from KB's to PF's can be covered by foot.
I don't think it exists in one piece any longer, and I don't think it traveled in one piece anywhere further than the ranch. Either it was burned on the farm if they have a commercial incinerator, or it was somehow utilized. Dogs or pigs are the first animals that come to mind.
However, I don't know how far will border collies go if they are not fed for a day or two.
Even cows eat ground remains, this is how mad cow disease got spread. "Mad cow disease spread in British herds in the mid-1980s after they were fed the processed animal remains of sheep infected with scrapie, a closely related brain-wasting disease." (CBC).
And if we have one lunatic who annihilated his family and hid them in oil, why can't we assume that another lunatic who killed the child's mother for no apparent reason could not do something equally horrific? The sole fact of such murder makes him capable of doing ugly stuff with the body. JMO.