Bloom :> "That's just language learning. These words have no special status as taboo words," says Paul Bloom, Ph.D., of Yale University. "Learning they're taboo words is a later step."

That's where it becomes really interesting to them.

(Hearing my three year old grandson say "what the heck!" at the appropriate moment really always pulls a laugh and he knows it; quite irresistable) that's half a year ago. By now , in preschool, he will be into the real stuff.