Not true. The Family Medical Leave Act (or FMLA-- Ha!) only applies to caregivers tending to immediate family, which is defined as a parent, child, or spouse. Just visiting a sister in the hospital doesn't qualify OP as a caregiver, and the sister doesn't qualify as immediate family unless OP's her legal guardian. There are also other restrictions; FMLA only applies to companies with 50+ employees, (excluding federal, state, and local public agencies, which have no employee threshold); and to employees who have worked both 12+ months and 1,250+ hours in the last 12 months at that job. Really, people, the internet is a big help with this stuff. It doesn't take long to check the facts before giving advice. =

Not to mention the fact that many states are "at-will" states, meaning that you can quit, or your boss can fire you, at any time, with or without reason. Although I'm not sure if Michigan falls into this category.