mcclane's law

the theory that as an online discussion about Christmas/holiday movies progresses, it becomes inevitable that someone or something will eventually be mentioned that Die Hard is indeed, a Christmas movie

{person 1}I think Home alone is the best Christmas movie.
{person 2}Nah, the Grinch is the best!
{person 3}What about Jingle All The Way?
{person 4}Did you know Die Hard is a Christmas movie??
{person 5}Hahaha, mcclane's law!