Not, of course, a tale in which one fairy tale happens to be coming true in a setting. One in which many do.
If it's only a handful of such tales -- Snow White, Beauty And the Beast, Sleeping Beauty, Cinderella, and maybe a few others -- the telling can get rather silly, since everyone knows what will happen. All part of the farce.
A setting with multifarious tales can make the dialog sound more realistic. I am quite certain that the hero and heroine will discuss what should be done if the bride or bridegroom is an animal that later sheds the animal skins -- because there's no way to know which way is right then. Burning it at once had been known to free the victim. It has also been known to force the victim to leave at once to marry someone else, and the true bride or bridegroom then has to quest over the land to find the victim again (though fortunately arriving in time for the wedding).
And they are sage enough to know that it's not their only field of danger. Leaving aside the notorious tendency to die in childbirth, a woman is in grave danger when her firstborn arrives. Her wicked stepmother may show up to murder her and put her own daughter in her place. And just because she has no stepmother doesn't mean that other villains can appear. A witch to turn her into a duck, perhaps. (Those who complain that the fairy tale always ends with the wedding -- should read more fairy tales.)
Telling fairy tales and foreshadowing at once -- nice to automatically get two things in at a time.