Elsa (Frozen) of the song "Let It Go", with critics frequently calling her a "powerhouse". Attempts were made as early as 1937 by Walt Disney to adapt Hans Christian Andersen's fairy tale, "The Snow Queen", into a film. The tale focuses on two children, one named Gerda, who served as the basis for Princess Anna, and the other named Kai, who is "cursed with negativity" after his heart is pierced with a shard of glass from an enchanted mirror and is later kidnapped by the Snow Queen. However, Disney struggled with creating a believable, multi-dimensional adaption of the fairy tale's title character,
Hans Christian Andersen he presumably fell in love with others. Other disappointments in love included Sophie Ørsted, the daughter of the physicist Hans Christian Ørsted and Louise Collin, the youngest daughter of his benefactor Jonas Collin. One of his stories, "The Nightingale", was written as an expression of his passion for Jenny Lind and became the inspiration for her nickname, the "Swedish Nightingale". Andersen was often shy around women and had extreme difficulty in proposing to Lind. When Lind was boarding a train to go to an opera concert, Andersen gave Lind a letter of proposal. Her feelings towards him were not the