I’ve had this stuck in my head for weeks, it was tacked on at the end of Little Red Riding Hood, the gruesome version (Charles Perrault) in which Red does not survive the attack:

Little girls, this seems to say,
Never stop upon your way.
Never trust a stranger-friend,
No one knows how it will end.
As you’re pretty, so be wise,
Wolves may lurk in every guise.
Handsome they may be, and kind,
Gay, or charming never mind.
Now, as then, ‘tis simple truth,
Sweetest tongue has sharpest tooth.

And of course we all know that the story was about much much more than a little girl being eaten by a wolf.