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Yes, employees CAN be employed in two different jobs, even though the "employer" is the same employer. The thing, though, is that if there is ANY overlap, the Department of Labor is going to treat it as a single employer. That is, if you have the employee work 30 hours in one job, and 30 hours in the next, if there's some sort of related work between the two, that would be treated as 60 hours, and if the employee is hourly, the employee would need to be paid overtime for that extra work. The two jobs would really have to be separate for the employee not to be paid overtime. You'd have the burden to show that they're really "different employers". Separating out the responsibilities towards the individiual jobs is important.
Furthermore, even though you're the employer in both, if the employee wishes to quit one job but not the other, you Really should accept that and not retaliate for the other job. The point is to treat it as though it really is two different jobs with two different employers. That's the best way to make sure that you're in compliance.
Hope that clears things up a bit. If you have any other questions, please let me know. If not, and you have not yet, please rate my answer AND press the "submit" button, if applicable.
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