He is immediately recognizable to Americans and kids of all ages across the world. He has been 5-and-a-half years old and more than a handful since he debuted in 1951, and he has never been out of print in some form somewhere. Whether he's making his father's hair turn gray, his mother reach the end of her rope, or making Mr. Wilson just lose it, Dennis is that part of our childhood we never want to forget Ð fun, with no consequences. In 1953 the series was already popular enough for a comic book, and our young friend has been appearing ever since!