You move on. To Alex, who writes, "Dear Santa Claus, thank you for the power ranger fighting battle station and I bet Tanner says thank you for the four wheeler. I don't know what I want for Christmas. I don't know what Tanner wants either."
You tell Alex and Tanner Welcome to the human race, because nobody ever really knows what they want. Even adults. We all just flail around wanting stuff, never satisfied, filling our gaping consumer souls with dreams of Bose stereo systems, unlimited gift certificates to independent book and record stores, courtside basketball seats, intensely sensual experiences that involve candles, wine, lotion, chocolate, um, never mind. Point being, stuff won't make you happy. Just listen to Britta, who writes, "I have been a very good girl this year, and I was sad today."
You will take her seriously. You will want to make her less sad if you can. You will also take it seriously when Chris writes only, "Just surprise me. Ho ho ho," and draws a picture of him and you with your arms around each other. You will take it seriously when Nathan asks for a present for his mom and dad and cat and a special nuk for the babies, and calls you "the best Santa that ever livd."
You correct Nathan, gently but firmly. You tell him that you are not the best Santa who ever livd, you are the only Santa who ever livd. Then you return the letters to Santa's helpers, who insisted you do so by "Christmas Eve, so Santa can do his job." Then you write them up in the newspaper and try to wash your hands of them, but you can't, so what you do is you put on your boots, feed the reindeer, and get ready to fly.