[bvw]

There are two theories that still hold water, imho. (1) that the murder/accident/suicide occured in the master bedroom in the presence of an improper sexual going-on, and that Damon and woever else was involved then went into this painful to watch unfolding cover up. (2) That Danielle disappeared -- was taken -- by some cult, who came to know the vD's through the swinging, and that her taking occured eariler in the afternoon, and perhaps at least one of the vD's -- D or B -- had given approval to it, but perhaps was deluded as to the sacrificial intent.

[bvw]

In support of the second theory, I'll mention the date of the disappearance, the missing sinister foot, and the disposal of the corpse in poison oak.

[RnMomof7]

What if Danielle wandered into the master bedroom while Barb and daddy were exchanging rubs that night? What if she got scared and started to yell for mommy..and they were afraid the other kids would hear ..what if they tried to quiet her and hit her ....and she hit her head......and accident that would also be child abuse..

[Lucky]

I can agree with your theories, or maybe it's a combination of your theories such as: the partiers also belong to a cult?