In Pueblo, Colorado, on a hot August day two sisters, ages three and six, and their 17-year-old baby sitter drowned at a mobile home park swimming pool that had no lifeguard.

We will never know exactly why this tragedy happened. There were other children in the pool at the time the sitter and her two young charges jumped into the deep end of the pool. A short time later a child was seen floating and others called for help. Attempts were made to revive them, but were unsuccessful. No foul play is suspected, and no criminal charges likely to be brought.

But this incident will remain a giant question. If you can’t swim, why jump into the deep end? Did they jump in thinking that there was no deep end, that the entire pool was only 3 feet deep? Did the little ones jump in and their sitter jump in to save them? It is unlikely that we will ever know the answers.