Wow, thanks Garry.
Your addition certainly adds some power to this story line.

Many years later one day swimming in a lake I left my young son with a gaggle of his cousins on the edge of the lake while I swam out about 40ft and turned to see him floating face down among his cousins (at least 4 or 5) and no-one not even the adults seemed to notice. Somewhere training had suggested staying calm so I called out “pick him up” but no-one reacted. It was on the 3rd occasion when panic must have crept into my voice that the adults who were on the bank woke up and ran to his assistance. In his case it looked like he had somehow fallen over on his face and was floating on his tummy with his face submerged in the water, but unable to right himself. It all looked so terrifyingly calm & horrifying in it’s potential consequences. Thank God in whatever form you choose to believe in one, he was reached in time and there was a nurse present among another small group that had visited the lake on the top of a mountain that day. So 2 example of just how easily & almost invisibly drownings can happens. Thanks Keith for highlighting this issue.