!!WARNING--GRAPHIC!!!!
Sorry, I have no evidence to back this up and it is just a theory, but here's a thought...
Perhaps KC was out partying and got drugged up and then passed out in the car with Caylee, or somewhere else, like a friends house alone with her or whatever. She passes out on drugs while the baby is sleeping and when she wakes up, the baby has too and found her stash of illegal drugs that she has left out irresponsibly. Caylee OD's and is already gone, or at least she gone enough that she thought she was gone.
She makes the frantic phone calls to mom the nurse and can't get in touch with her. Heads to the house and finds them not there, but it is familiar so she backs into the garage, she stashes the body in the sandbox, but it is not deep enough so she moves it to the playhouse until she can figure out what to do. Realizes the parents are out of town for a few days and stashes her in the freezer (Still trying to find out if there was a deep freezer in the garage). Remember they did not release (to my knowledge) the calls from June 17th.
I believe a freezer had to be involved here somewhere because the car supposedly did not smell as bad as the other that had a body in it and the neighbors did not report smelling anything. This is assuming that before she dumped the car at Amscott that she had just hid the body again. I don't give it much time before that. Orlando is HOT in June folks. I don't think that if a freezer was not involved that the body would be in the kind of shape that you would want to be moving around after 10 days. Although there is the garbage bag and strange stain. Garbage bags do leak.
Anyway, thinks to burn her and borrows the shovel to get into the shed and steal the gas cans. Then mom and dad are coming back and she has to get everything out of there, so she comes back and gets the body and takes it somewhere and burns it or disposes of it in some way and goes back to "normal life".
Honestly, I have said this before. I think the girl is so absent from reality that she doesn't even see Caylee as her child anymore in her mind. Like that child she obviously moved, probably more than once, in her head wasn't hers at all and in her mind she is just telling herself that she is with the babysitter.
Dante is still bothering me as well. DId he ever talk to LE? Has anyone ever mentioned this again?