What's your illness?

 I'm blessed with robust health, and the only illness I get is the occasional bout of irritating flu.  But illness in characters can be a strong driver for their actions.

At the start of Panthera : Death Spiral Ren is trying to work out why three otherwise healthy kingcat cubs have suddenly died.  She discovers that they died from immune system failure, caused by somebody taking away their thymus gland cells.  In Panthera : Death Song, young and powerful jagotheras are dying inexplicably from heart attacks.  In both books, the big cats' illness is what drives the story,

In Eyemind, it's human illness that drives the plot, in the form of a partly physically disabled psychopath 'getting his own back' on the world that created him, and hurting a lot of innocent people along the way.

One of my must-have books is The Writer's Guide to Character Traits, by Linda Edelstein, PhD.  This is a gold mine of information on personality types, and lists the traits and symptoms of a whole range of physical and mental illnesses.  I found it really useful to beef up the traits of my psychopath villain.

Your characters' illnesses might define their lives by stopping them doing what they really want to, or their story might be a tale of overcoming that illness to succeed.  Or their illness might be one that leaves a trail of destruction in other people's lives.  

Illness can be a powerful motivator of actions, and shaper of stories, so next time you need to give a character an extra struggle, consider making him or her ill.