What is Kristen book about in The Clique series?

With the rest of the Pretty Committee far from home, Kristen is clique-less in Westchester for a summer of solitude. But when she scores a job looking after hang-ten hottie Dune Baxter's eight-year-old sister, Ripple, her stay-cation suddenly doesn't seem so bad. Suddenly, Kristen goes from bored to board as she rides the wave of first luh-v.