Hi, I am new to the board, but have been following the case and reading websleuths since the story broke in July.
I have thought about this case carefully and there's an eerie resemblance of a flat effect of Scott Peterson and Casey but back to the point of the Grandparents seeking immunity.
I absolutely agree with you, that the grandparents have knowingly interfered with the case.
It defies logic.
If your grandchild is missing wouldn't you want the police and FBI track down her whereabouts? To seek the truth no matter what it was? Why would you give the wrong hairbrush and toothbrush? Also, to refuse to help Tim Miller and Equasearch with a piece of her clothing?
There's no logical answer to this.
From the interviews I saw not once did the grandparents, Lee or Casey use the media to appeal to the kidnapper to return the child either.
The only logical answer is that they knew that something happened to Caylee by the hands of the daughter and tried to interfere with the investigation to throw the police off.