Harry Potter fan theory shows how Professor Trelawney may have predicted Dumbledore's death

Reddit user xAnuq makes the case that JK Rowling drops a major clue in her third novel Prisoner of Azkaban, way ahead of the Hogwarts headmaster's death in book six.

At Christmas, as this Harry Potter fan points out, almost everyone in Hogwarts has gone home for the festive season - that is, except for a small group of staff and students who are eating lunch together. When Trelawney shows up Dumbledore offers her a seat at the table, but she's horrified.

In the book, she cries: "I dare not, Headmaster! If I join the table, we shall be thirteen! Nothing could be more unlucky! Never forget that when thirteen dine together, the first to rise will be the first to die!"

There are twelve people sitting at the table already - that is, Snape, McGonagall, Spout, Flitwick, Filch, Dumbledore, three students, Ron, Hermione and Harry. Or are there?

"In order to calm her, Dumbledore stands up and leaves the table," the Reddit post explains. "But we later get to know that Ron's rat [Scabbers] was just Peter Pettigrew who transformed himself. Knowing that Ron carried his rat in his pocket most of the time, that'd mean there were already 13 people at the table. As Dumbledore leaves as the first of those 13 people, his fate was sealed."

Looking at Chapter 11 of the novel itself, the moment could actually come when Dumbledore politely welcomes Trelawney to the table: "'Sybill, this is a pleasant surprise!' said Dumbledore, standing up."

That's not a problem - unless Pettigrew was also at the table in Ron's pocket.

Did Dumbledore seal his fate? And is this another excellent example of foreshadowing by JK Rowling?