This is a Hawaiian legend dealing with the Menehune or night walkers which are small spirits.

One day a family in Hawaii decided to build a wall around their garden. After it was done the parents could see their son sitting on the wall and it looked like he was having a conversation with himself. They asked him what he was doing and he said the Menehunes or night walkers were upset because they wall stopped them from being able to walk through the garden. The Menehunes were small spirits who were known to cause problems if given a reason. Not wanting to upset the spirits the family went to a Kahuna to see what they should do. The Kahuna told them to do two things first to put salt on the four corners of the wall as a defense measure and secondly to cut a small hole in the wall for the Menehunes to walk through. The word of the Kahuna proved true as once those steps were taken the family had no further trouble from the Menehunes.

This seems to be a typical ghost story with a local twist as the Menehunes are spirits particular to Hawaii and actually were only seen post interaction with the western world. This story also features the powers of a wise person in order to keep the wrath of the spirits at bay showing that people can forestall harm to themselves if taking the proper steps. This element makes people respect the supernatural while giving them the steps to protect themselves.