Also, if you don't try to keep your developers happy when something happens, even good developers, they can easily jump ship to another company that does & maybe even get paid better - health issues are nothing to be trifled with, they happen to everyone & good companies will give time off for such for good reason. Even the military with its notorious overworking of people makes sure people have ample time off to recover from illnesses before making an action.
It's by far a pro-developer's job market - I'm looking at about a $70k+ raise in income + stock options over the past 6-7 months with little more than 1 year of experience (from entry level pay & no CS classes in education). If craziness like that can happen, you should beware pushing your developers in the wrong ways since jumping is an attractive option.