Factual error: When Cecelia and her friends are in the car, following Aquamarine, Hailey, and Claire to the water tower, they aren't that far away - probably less than thirty feet - yet the other girls don't hear their car approaching.
Factual error: The film is based in Florida but several scenes show rocky cliffs and hills not native to the area.
Answer: The media circus that would surround the discovery of a real life mermaid would threaten the girl's goal of trying to get Aquamarine and Raymond to fall in love. It's exactly what Cecilia tries to do when she discovers Aquamarine's secret.
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