She didn't get sick again, she took another job (I must have accidentally edited that part out)
I think the article assumes Jill did something that caused her to want to leave (she found a new job, networked and someone offered, etc...) but maybe it was the employer? The employer could have challenged her on time off compensation, insurance coverage, etc...
So my answer to this would be - to a person, as much as they deserve. But to a company, as little as necessary.
>>Your loyalty should be a reflection of your employer’s loyalty.
A company a group of people after all. It's easy to think about our jobs as benefits acquired for services rendered rather than a relationship with a group of people.