Found the following article online, use it to answer the question: What is the name of the character who has lost the will to live?

The film starts off with a scene from the novel Moby Dick, with a whaler on a stormy sea in the 19th century, chasing "the white whale". It turns out that the scene comes from the imagination of Dot, while she is sitting with the book. She goes out to play with Nelson the dolphin in his pool, and he teaches her how to stay underwater for long periods of time and to communicate underwater, as well as the history and evolution of sea creatures.
While they play together, Nelson hears the wail of a beached whale named "Tonga" from the local coast, and jumps out of his pool, over the cliff beside, and dives into the ocean on the other side, to check what is going on, with Dot coming along. Dot walks up on land to talk with Tonga, but becomes upset as two boys, Alex and Owen, stand and throw sand on the whale. The boys say that they only want to push the whale back to the sea. Together, they try to push Tonga back to the water, but fail. They decide to gather as many kids as possible, in order to help the whale as much as they can.
While Alex and Owen start to gather help, Dot sits beside Tonga, trying to converse. Tonga explains that her family has been killed by whalers, and she is the only survivor, but has lost the will to live. Dot explains that she and others want to help Tonga, and tries to by having Tonga placed in the same pool as Nelson to let her recover. Dot then realizes that they do not have a transport facility for a whale. Meanwhile, a crooked fishmonger becomes interested in Tonga as a possible "Fish" source.

Tonga