I just checked my hair dryer. I can plug it in above the vanity and it will touch the bottom of the tub. If my 5 year old angel lived here, I would cut the cord a few inches below the GFCI module. I would shorten the cord and splice, solder and heat shrink it so it couldn't reach the tub without yanking the plug out.

I'm not saying that this happened in this case but in today's society, more and more barbarians are murdering their children rather than finding loving homes for them. They say that many cases of SIDS are really murder. Not too far from me a woman murdered her two small children and actually set her home on fire to cover it up. So whether it's a cop's 3rd wife drowning in an empty bathtub or a child being electrocuted in one, I sure hope there is physical evidence on the scene to support it.
Joe