Not a personal bad experience, but I was more than disgusted.
A couple decided to leave their infant baby sleeping in a stroller while they went to go ride Indiana Jones. I walked by during the end of the commotion, but it was enough to see that the poor little girl was almost sunburnt to a crisp. Park security was escorting the parents away (hopefully to be arrested). The argument I heard was that it was their child and free to do what they liked. I wanted to punch them in the face!