Unappreciated

Evelyn is just a girl living with her brother James, her Mom, and her Dad. Her Dad is always at work, but when his boss gives him 4 plane tickets to Dolphin Island, she doesn't sound very happy about it, until she meets her new best friend. What do you think her new friend would be like? WHO do you think her new friend is? A he? Or a she? Or is it just some sort of animal or better yet, her imagination.