Is there a particular significance to the death date of October 31 for J.K. Rowling? I noticed both Nearly-Headless Nick and the Potters were killed on Halloween. Are there any interviews or chats where J.K. Rowling discusses this?
Large, rotten fish were laid on handsome silver platters; cakes, burned charcoal black, were heaped on salvers; there was a great maggoty haggis, a slab of cheese covered in furry green mould and, in pride of place, an enormous grey cake in the shape of a tombstone, with tar-like icing forming the words, Sir Nicholas de Mimsy-Porpington - died 31st October, 1492
Chamber of Secrets - page 102 - British Hardcover
[The headstone] was made of white marble, just like Dumbledore’s tomb, and this made it easy to read, as it seemed to shine in the dark. Harry did not need to kneel or even approach very close to it to make out the words engraved upon it.
James Potter, born 27 March 1960, died 31 October 1981 // Lily Potter, born 30 January 1960, died 31 October 1981 // The last enemy that shall be destroyed is death.
Deathly Hallows - page 268 - British Hardcover