I am not a lawyer but I have read something about water being an attractant. Your float could be what a lawyer would say caused the child to go into the water. But a child that gets out is better than one that drowns.

61 acre water shed lake. bass, channel cat, black crappie, wiper, walleye, redear sunfish, blue catfish and bluegill. To many bullhead and common carp
http://www.pondboss.com/news/videos/why-subscribe-to-pond-boss