I've been wondering for a while now if there is anything you can mix in food or (preferably) drinks in order to make it flourescent (when exposed to visible or UV light), without it also becoming toxic at the same time. I'm looking for generic things, so no specific brands (as it is quite likely that we won't have it here). Vitamin B12 is the only one I know of, but there has to be others.
This person did not, and "my" dog died before I turned 5 But I would be surprised if everyone actually knew that. I've been asking around among my friends for other things that would fit the bill, and not a single one suggested GT. It might also be a regional thing, almost everyone in a certain part of the world know something like that.