R. L. Stine Tells Saddest Halloween Childhood Story Ever

Grab your tissues, everybody ... R.L. Stine -- the author dedicated to scaring kids -- has a tearjerker of a story.

We caught up with the "Goosebumps" author Friday in NYC where we asked him for tips on Halloween costumes. Check out the vid ... R.L. gets all heartbroken telling our photog about the costume he was forced to wear as a kid.