In an ideal world, doing business with your family members would be both a risk-free and rewarding experience. But in a read world (and I'm saying this 'cause I worked with some of my relatives in the past), the benefits it brings are infinitesimal compared to the challenges you are faced with. (And, unfortunately, I'm not the only person who says so). First, relatives often expect to have extra freedoms and preferential treatment. I think it's human nature for us to want to take advantage of being a part of the family in order to ask for time off, miss deadlines, come in late, or go home early. Even if you're insanely lucky and your relative doesn't act like this, you may be afraid that your co-workers will start thinking that your relative is getting preferential treatment. As a result, you could be overly critical of them or assign them even more responsibilities, which your relative might not appreciate 'cause it's unfair. However, you may become overly protective of your family members and start going easier on them when they are having a hard time. Because of this, you will pass their responsibilities to other co-workers, which is unfair as well. If you work with your significant other, you will face challenges too 'cause you won't have enough time alone, and it will be really hard for you to keep your family life separate from your work life. In the long run, this can significantly damage your relationship and turn spending time together into a chore to endure. And I could go on and on. But it's all true.