OK, then how does a child drown in a pool? At the very least you have negelect, and all the other crimes dealing with handling of a corpse/human remains.
Accidents happen - children have been drowning since the dawn of man.
No one has any problems with her being charged with the post-death actions. I will say that society would be much better off if she received some competent mental health treatment - putting her in regular prison for those other charges isn't going to help anyone.
She is a sociopath, there is no treatment for someone who lacks empathy for others. She thinks she can steal,lie, cheat etc, because others are foolish enough to beleive her. As a point of fact, she is the perfect example of evolution, she is the fittest among us, because she can manipulate others around her for her benefit.