was there any blood involved?
no
Did someone accidentally hit her with a paddle and she fell in the water? no
Was she grabbing at the possibly wooden boat to try and get back on it? why would it be wooden? Uh, no
Can she swim? yes
I believe that leaves "Ocean," right? yes
Was there water-skiing or surfing involved? no
Was she conscious while drowning? yes
Was there any sort of poisonous fish involved? no
She dropped something in the water (possible the child) and then took off her clothes and jumped in to get it, however she could not get back in the boat and was clawing away at the sides? nope
Or she went for a swim and couldnt get back in the boat and was clawing away at the sides. ooh, close. Now you only lack why she couldn't get back in the boat
Are pirahnas involved in any way? no
By nails were you talking about fingernails? yes
Were her nails damaged due to trying to climb something that she could not climb? yes
Was the murderer also in the water with her at any point? there's no murderer
Was the time of death in the dark hours? irrelevant