The Big Sister Organization wants Alexa to do a billboard featuring one of their big and little sister success stories: Kelly and Kristin. When Alexa finds out that Little Sister Kristen's birthday is right around the corner, she has the Fairies plan a surprise party for the end of the shoot. Plus, Alexa feels inspired and decides to give back by volunteering her fairies for community service in Hoboken to beautify the neighborhood, but instead, they get assigned to do something far less glamorous.