Mermaid Park by Beth Mayall

Amy , a swimmer, has a rocky relationship with her Mom, sister and her stepdad. They take a vacation to the beach to see Lynne, her mom's godmother. One bad event leads to Amy staying at the beach for the entire summer. While wandering around, she finds the Mermaid Park. An amusement park of sorts that puts on a mermaid show. With her love of swimming, Amy just knows she has found the perfect summer job.

I actually expected this to be a more magical story. I really didn't enjoy it much. Amy is a wishy washy character who allows her mom to pick her stepdad over her. She doesn't really stick up for herself, even though it's obvious her stepdad is verbally abusive. Her relationship with her sister is strained, as she finds out Mel, lies about everything in her life.