[Schneed10]

I used to lifeguard in the summers between college semesters. In our training classes they warned us about this. They always told us that if you see a kid submerged and then pop up gasping for air, it's important to keep a close eye. Sometimes kids dunk each other, and sometimes they pin each other underwater. Kids being kids, but if someone stays under too long they can take a big breath of water, and it can cause problems if they don't cough enough of it up.