[jet]

It still means there was a limited time frame to hide Maddies body so thoroughly that it has never been found in what is really a limited seach area if it was them that caused her death.
....and as the kids were all playing together before bedtime, either or both of the McCanns would have to have been missing from the meal for quite some time in that case....
Much more likely that she was taken and driven far away by a stranger.