Want to know how intense the 49ers/Seahawks rivalry has gotten in the last year or so? Just read this letter that a 6-year-old San Francisco fan wrote for the Seahawks recently:

If you can't read it, it says: "SEAHAWKS, A SEA SERPENT IS WATCHING THE GAME. IF YOU WIN, IT WILL EAT THE FANS AND EAT YOU. A VIRUS WILL COME INTO YOUR THROAT AND GIVE YOU THE FLU. YOU'LL PROBABLY NEED A FLU SHOT AT FRED MEYER. NO SEAHAWKS BEYOND THIS POINT."

This letter is: A) Just about the cutest thing that we've ever seen a 6-year-old write, and B) Just about the most threatening thing that we've ever seen a 6-year-old write. Also, it makes us really hope and wish and pray that the Niners meet up with the Seahawks in the playoffs. That playoff game would obviously be epic—sea serpents and all.

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[via Deadspin]