via WMBF News:
A leading cause of death in children is drowning, and home swimming pools are the most common place for a child younger than 5-years-old to drown.
Approximately 400 children age 14 and younger drown each year in pools and spas, and most were under adult supervision before they drowned.
Additionally, Slate.com has a great article on how "Drowning Doesn’t Look Like Drowning" a few of the things to keep in mind and look out for are:
1) “Except in rare circumstances, drowning people are physiologically unable to call out for help. The respiratory system was designed for breathing. Speech is the secondary or overlaid function. Breathing must be fulfilled before speech occurs.
2) Drowning people’s mouths alternately sink below and reappear above the surface of the water. The mouths of drowning people are not above the surface of the water long enough for them to exhale, inhale, and call out for help. When the drowning people’s mouths are above the surface, they exhale and inhale quickly as their mouths start to sink below the surface of the water.
3) Drowning people cannot wave for help. Nature instinctively forces them to extend their arms laterally and press down on the water’s surface. Pressing down on the surface of the water permits drowning people to leverage their bodies so they can lift their mouths out of the water to breathe.
Head over to Slate.com for their full article