There is not one shred of evidence to support that theory.
That is true, although technically the fact that the child is dead does support the theory that she drowned. I’m not saying that the story is true, just that their story does, if true, answer the objections given here about why the mother didn’t report the child missing.
It is the story the defense told, so to the jurors, if they accepted the defense claim of drowning, they would not have any issue about why Casey didn’t report the child missing.
And apparently the body decomposed for so long that the medical examiner couldn’t rule out drowning as the original cause of death, just as he couldn’t prove there was chloriform, which was the Prosecution argument, backed up by a faulty web search analysis, as we now know from this article, and which the Prosecution knew before the trial ended but never mentioned.
Again, I’m not saying the defense wasn’t lying.