Not to scare anyone but this happened in my neighborhood this past Saturday....a 10 yr old boy drowned a number of hours after going home from the pool (called secondary drowning). Appears the boy swallowed a large amount of water. This secondary drowning occurs when water enters the lungs and washing out a liquid called surfactant, which keeps the airways open. This can happen upto 24 hours after ingesting the water. Please watch your children and be aware of any abnormal symtoms like difficulty in breathing or unusual sleepyness after swimming.