Final answer:
The individual believed to kidnap children in Gavaldon is fictitious and not directly related to the provided text excerpts, which refer to other supernatural or mysterious events.
Step-by-step explanation:
The character believed to kidnap children every four years in the town of Gavaldon is from a fictional tale and does not correspond directly to any of the text excerpts provided. However, this question seems evocative of fantastical or supernatural stories where characters like the Galloping Hessian from Washington Irving's "The Legend of Sleepy Hollow" are considered to be the culprits in mysterious disappearances.
Such stories often feature elements of folklore, myth, or local superstition fueling the imagination of people within the story to come up with various theories regarding unexplained events.