Princess Marisa is a Sirena princess who appears in the Elena of Avalor special, "Song of the Sirenas".
Background
Many years ago before Marisa was born, the Sirenas used to sink human ships. However one day, Marisa's father, King Pescoro of the Sirenas, saw a woman named Camila drowning. Feeling guilty, Pescoro saved her by wrapping her in magical kelp that turned her into a Sirena, and the two fell in love. From that day on, the Sirenas never again sank human ships.
Due to Marisa's mother, Camila, being originally human, she and her brother, Marzel, are half-human and half-Sirena, allowing them to turn their tails into legs when they are on land.
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