Oh my! Her and the family are in our thoughts and prayers!
I heard that sharks and alligators were about the same - the can attack in the shallowest of waters and not be noticed - how, I do not know. There was a story not long ago about a toddler that was playing in the shallow waters of a sandy bottomed area (water not even to her thighs) and a big gator got her. How horrible!!! You just never know!!!