Arnold (on the left) with Gerald and Helga in "The 12 Days of Nickmas".
Arnold Phillip Shortman is an animated character created by Craig Bartlett for a series of clay animation short films (one of which was used on Sesame Street), and the titular protagonist of the Nickelodeon animated series Hey Arnold! He is a young boy who lives in the Sunset Arms boarding house with his paternal grandparents. He is a calm dreamer and an idealist who always looks on the bright side and tries to see the best in people. Whenever he sees someone in trouble, he goes out of his way to do the right thing and help them out, even if it is not sensible to do so.
Appearances in Christmas specials
Hey Arnold!
Arnold's only starring role in a Christmas special was, naturally, the Hey Arnold! episode "Arnold's Christmas". In it, he is assigned to be the Secret Santa for his fellow boarder, Mr. Hyunh, whom he notices is always depressed around Christmas time. When he talks to Mr. Hyunh about what he would like for Christmas, he learns that all Mr. Hyunh wants is to be reunited with his daughter, Mai, whom he had given up to be saved by American rescue soldiers during the Vietnam War. On Christmas Eve, accompanied by his best friend, Gerald Johanssen, Arnold goes to the Federal Office of Information to find out where Mai currently lives. The supervisor, Mr. Bailey, only agrees to help if they can do his Christmas shopping for him. They manage to do so, but are unable to find the last item on the list - a pair of Nancy Spumoni snow boots. When they tell him they could not find them, he refuses to find Mai, and Arnold goes to bed feeling sad that he could not grant Mr. Hyunh's wish.
Unbeknownst to Arnold, however, his bully/secret admirer, Helga Pataki, who has been trying to find the perfect thing to give him, overheard him talking about how he wanted to make Mr. Hyunh happy, and she has just received a pair of Nancy Spumoni snow boots from her mother, Miriam. She comes to realize that making Mr. Hyunh happy is the perfect gift for Arnold, so she gives her boots to Mr. Bailey and gets him to locate Mai. When Mai arrives at the boarding house on Christmas morning and reunites with Mr. Hyunh, Arnold is pleasantly surprised and puzzled as to how this miracle happened.
Other Christmas productions
Arnold also appeared along with Gerald and Helga in the Merry Nickmas interstitial shorts. In a rather fitting return to Arnold's roots, they are shown in stop-motion animation in "The 12 Days of Nickmas", where they sing the line "Three cans of hairspray," and taking part in the festivities in "Holiday Party". He and Gerald also appear among the citizens of Toonville in "How the You-Know-Who Stole You-Know-What!"