The girls had arrived with their trousseau (Meaning the outfit of a bride, including the wedding dress or similar clothing) which was shaped unusually very much like traditional coffins. So mockingly the girls acquired the name of Casket Girls. Their trousseaus were placed in the third floor attic of the convent, and were not retrieved until a proper suitor was found for each girl.
However, when the trousseaus were retrieved they were mysteriously found empty. Superstitious individuals of the time claimed that they girls had smuggled vampires here to the French Quarter.
Well, that's the legend, as it’s been passed down. But if this is just a legend, then why does the convent to this day seal each upstairs window with 8000 blessed screws? And every so often one of the windows will shoot open for no apparent reason, and immediately the convent once again seals it shut.