This week, NYCB is bringing back “Harlequinade,” Balanchine’s 1965 remake of the Petipa ballet “Les Millions d’Arlequin,” with Joaquín de Luz in the title role. Like his “Nutcracker” and “Coppélia,” “Harlequinade” is a nostalgic look at another age, the cozy world of 19th century fantasy ballets. And like those other works, it’s full of children. See my review of last night’s performance here.