What do you do with your protagonist if you’re writing a popular series of books that lasts over a period of decades? Do you let him/her grow older? Michael Connelly’s Detective Harry Bosch has aged in real time and will be sixty in the new book due out this fall. Sue Grafton’s Kinsey Millhone is aging more slowly, roughly one year for every 2½ books. But aging hasn’t always been embraced. Raymond Chandler’s Philip Marlowe remained steadfastly in mid-life; James Bond hasn’t aged a day. Read more about a successful author’s dilemma in an article by Alexandra Alter for the Wall Street Journal.