Aren't you just a little quick to judge. I didn't read any facts in the story that would lead me to believe this was anything other than an accident. I really can't see how the boyfriend is an idiot.
They are both idiots (mother and bf)....an unattended 5 year old girl on a dock says all it needs to say. If she was being watched properly, then a stranger DID NOT have to be the one to jump in and save the girl.
I'm with you- as a single dad of 3 little angels I live in constant daily fear of the minor error that turns into major catastrophe.
Letting a 5 year old play on the edge of a dock when you aren't there to supervise and rescue her yourself qualifies.