What episode is the little princess Sophia becoming a mermaid?

Sofia First is a series of cartoons produced by Disney. Tell the story of an ordinary girl slowly learning to become a real princess. This series of cartoons makes children understand that through hard work, they can become real princesses, and understanding inner beauty is more important than appearance. At the same time, at the Royal Preparatory College, three fairy godmothers taught Sophia the qualities she needed to become a new generation of little princesses. As the newest princess created by Disney Company, Sophia is not just waiting for redemption and pursuing true love like a traditional princess. She also encourages the little girl to affirm and cultivate her intrinsic value, learn to play empathy, and then show positive interpersonal interaction, stick to her self-belief and use it to accept various challenges. This brand-new idea was quickly welcomed by the audience, and Princess Sophia's cartoon became the champion of children's programs in 149 countries and regions.