Maybe he wrote something from Phoebe's point of view...

According to the New York Times, J.D. Salinger's estate may release up to five more books written by the late author, including additional stories about the families of his most famous creations, Holden Caulfield and the Glass family (featured in Franny and Zooey and Nine Stories). I'm still taking this story with a grain of salt, but the article claims that the upcoming documentary Salinger, due out early next month, will explore Salinger's request that his estate begin publishing the books as early as 2015.