Today's Halloween costumes seem to mimic far more than the traditional big-skirted and glittery costumes of Disney style princesses and some kids Halloween costumes are actually styled after actual living members of the royal family. The strange hat worn by Princess Beatrice during the recent wedding of the Queen's grandson is a popular and weird design that's started to show up in costume stores in a variety of sizes so that it can be worn by everyone from small kids who want to be a princess to older celebrants who think the completely weird hat is a great Halloween option.