This doesn't sound that odd to me. It may turn out tragically, but I don't find it odd. A family was having an outing in a park with woods and water, and a child went missing. People do drown in 4-5' of water and people do get lost in woods.
A 12 year-old doesn't need to be watched constantly, and I sure wouldn't call the cops until I had searched everywhere I could think of, and it started to get dark. I had sips of beer and wine at this age and younger, with my parents. I don't see why that even got included in the story.
I feel for the family. My 10 year-old daughter and I just returned from a family reunion weekend at a lake. There were lots of kids, adults, water, boats, and beer. Everyone is fine, but could something like this have happened? Yes.