(Note that you can drink a lot of pure heavy water without worrying about any health impact. I still wouldn't recommend it, but bad things would be unlikely to happen by accident.)
> You could consume a single glass of heavy water without suffering any major ill effects, however, should you drink any appreciable volume of it, you might begin to feel dizzy. That's because the density difference between regular water and heavy water would alter the density of the fluid in your inner ear
> magic heavy chemical water with different nuclear properties...
That seems a bit dismissive. I would naively assume that there have been exactly zero studies to see if there are any problems with babies drinking heavy water, beyond some LD50 extrapolation.