People tend to check in during these times:
Make a wish on her tomb and leave an offering. Have a little respect and don't mark on the grave. This is nothing but vandalism.
The tomb with the plaque is not actually Marie's. follow the asphalt to the left to the wall and find her real, unmarked grave with the offerings on it.
Anywhere between 175 and 225 people could be buried in a tomb like Marie Laveau's!
Persons marking on the Laveau tomb, or any other edifice within the historic New Orleans cemeteries, may be subject to police action.
Whatever you do... do it three times.