Dear Miss Princess Celestia,
I hope you get this letter okay. Not really sure how you get yer mail, but I'm gonna wrap it nice and fancy so they know it's for royalty. Wouldn't want it to get lost.
Ma and Pa said to send you this letter because it's Family Appreciation Day. They said you like to get letters from fillies and colts across Equestria so you can see how happy everypony is. I think that's mighty sweet of you, Princess.
Now, how do I start this thing?