i still can't believe the drowning theory.. drowning would have been perfect for Casey. Nothing to cover up and very hard to prove someone is at fault for a 2 year old drowning.
Try and think like this.
Your parents have told you they don't want any of your friends at the house while they are gone. You call a few friends over, drinking...some pot...having a good time......people leave...maybe one stays who knows....but your high, maybe took a pill or two....and your kid drowns.....you know your going to get tested, you know they can tell the time line of when someone drowns so you freak out and hide the body and make up a story. But you wait so that when the body is found, in the heat of Florida it;s impossible to tell how the poor child died.