I can't imagine what was going through this father's mind in letting his son play in the water at such a time.
Unfortunately, people don't think about things like this in many cases. It's Disney. It's the "Happiest Place on Earth." They have animals like in a zoo. Surely they wouldn't let anything dangerous get in here. It's right by the hotel. It's shallow water. Nothing can happen.
People think that way, unfortunately. Tragic situation. Preventable, though.