A lifeguard's warning for all parents: Would you notice the hidden danger in this image?

At first glance, the photo below shows a group of children playing in a popular public pool on a summer’s day.

But look a little more closely and one of them is in trouble. Can you see him?

YouTube/Lifeguard Rescue

How about now?

YouTube/Lifeguard Rescue

Thankfully, the trained lifeguard on the side of the water spotted the flailing child who's fallen from his inflatable tube just moments after it happened and quickly comes to his rescue - you can watch the video above.

The footage from 2015 comes from Whirlin' Waters Adventure Park in North Charleston, South Carolina, where a few years ago manager Kevin Rowlands set up a poolside camera because he wanted to show his lifeguards just how easy it is for a child to get into trouble in the water.

His YouTube channel, Lifeguard Rescuehas nearly 50 videos of rescues, some with tens of millions of views, like the one above.

The most recent video was posted just four days ago and shows a female lifeguard coming to the aid of a small child, struggling despite being surrounded by dozens of others.

The videos also provide an important reminder for parents to provide proper supervision a few seconds of inattention can be the difference between life and death.

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