All Hallows Eve

Since our earliest ancestors, we have wondered what secrets are held beyond our own death. On Halloween night the veil between the living and the dead is at it's thinnest so take my hand and let's take a walk into the darkness, but whatever you do, don't let go because hidden in the darkness are things that the living are not supposed to see.  

Barbados, late 18th Century, and the lifeless body of Elizabeth Elliot is laid to rest in the family tomb before an enormous blue slab of marble is pushed across the entrance to seal the tomb.
A few years later, falling on hard times, the Elliot family sold the vault to the Chase family and the first member of the Chase Family to be buried there was Mary Anne Marie Chase who died at the age of two in 1808.
Her small lead coffin was placed in the vault alongside Elizabeth Elliot's and the marble slab was pushed back into place where it would remain for four years.
In 1812 Mary Anne's older sister, Dorcas, died and her coffin was added to the vault and a month later the head of the family, Colonel Thomas Chase, committed suicide but when the pallbearers opened the vault a grisly sight met them all. Inside the tomb, both of the little girl's coffins had been seemingly thrown about and were lying in a haphazard fashion on the vault's floor but Elizabeth Elliot's coffin was untouched.
Blaming grave robbers, the two coffins were straightened and the body of Colonel Chase was added before the vault was sealed once more.
Four years later, the vault was once again opened to admit the body of eleven year-old Charles Brewster Ames and again, with the exception of Mrs Elliot;s, the coffins inside the tomb had been thrown about. 
By now, the story had begun to spread around the island and 52 days later when Samuel Brewster was due to be buried, the vault was inspected from the outside for anything out of the ordinary.  The found that the vault was airtight and watertight and that nothing could get in or out however, upon opening the tomb, once again they discovered that the coffins had been violently disturbed, all except Elizabeth Elliot's.
By this time, the news of the moving coffins had reached the ears of Barbados' governor, Lord Combermere, who ordered that the vault be inspected and made impenetrable from the outside. He then ordered that sand be sprinkled on the floor so that footprints would betray any human or animal intruders.  Finally, the governor's seal was placed into the fresh cement of the vault seal as an added precaution. 
For two years this is how the vault remained until slaves working on a nearby field heard strange noises coming from the vault.
To quash rumours of restless spirits, Lord Combermere ordered the vault to be opened but as the marble slab was removed, the crowd gasped as what was revealed was the coffins once again moved around and some laying on their edge. There were no prints in the sand so no-one had entered the vault.
To avoid further panic, Lord Combermere ordered the coffins be buried in a churchyard and the vault left empty and that is how it has stood for the past 200 years, nobody daring to tempt fate by allowing a family member to be buried there.

Maybe the disturbances were caused by earthquakes, hoaxers or maybe the vault was prone to flooding which had lifted and dropped the coffins as the vault filled and emptied of water. Possibly the answer lays with something more sinister that stepped onto our side of the thin veil.
Sleep tight and don't worry that sound outside, it's just the wind. Probably.