The Little Mermaid 2: Return to Sea

Melody - daughter of Ariel and Eric have been told to get away from the ocean since she was a little kid. But the fact is, she can't resist the water and has been swimming for a long time. Morgana, sister of Ursula takes the chance to make a deal with Melody. In exchage for her wish of becoming a mermaid, she must steal her grandfather's triton.