One of the difficulties in writing fiction is how to individualize your characters to make them real. This can be achieved through dialogue or specific character tics or mannerisms. Doing this in a series is more difficult because you have to keep the characters consistent in book after book. One of my favorite series—and I qualify this because I’m not a big series reader—is Michael Robotham’s Joe O’Loughlin series. Joe is a clinical psychologist with Parkinson’s Disease. Robotham doesn’t hit the reader over the head with the disintegrating effects of the illness on Joe’s body. Instead, throughout the series, the symptoms become more subtly noticeable: a disobedient leg that freezes in mid-gait or a hand tremor, but never does he make the character about the disease or the disease about the character. To coin one of my least favorite phrases, it is what it is. Joe goes about his business solving crimes without ever becoming a victim. I can think of two series where the character...