Messner, Kate, The Seventh Wish.
Charlie feels like she’s always coming in last. From her Mom’s new job to her sister’s life away at college, everything else seems more important than Charlie’s upcoming Irish dance competition, her science project, or how much she misses her sister. One day, while ice-fishing, Charlie catches a fish which offers to grant her a wish in exchange for its freedom. The most serious plot point involves the discovery of her older sister’s heroin addiction, and her subsequent treatment.