An Unexpected Birthday

Luna Winters is turning 18 and has a dance audition she practiced hard for. Her brother Sawyer Winters is treating her like a princess, but cold step-brother Kurt Wolffe who seems to have a disliking toward her is being as annoying as ever. Will she be able to make it in the dance troupe and fix her relationship with her step-brother?
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"Reviews":

I was starting to run out of older brother books to read, but as soon as I picked it up, I couldn't put it down! - The New York Times

Best book I have ever read -The Washington Post

My favorite book on the market!!! - Shriya Bhaskara (an older brother-book expert and enthusiast)