Utilize your financial knowledge, give your answer or opinion to the input question or subject . Answer format is not limited.

Is it legal if I'm managing my family's entire wealth?
Aside from the fact that there are massive problems with taxes, liability, fiduciary responsibility, and (assuming you're accepting any sort of compensation at all) licensing. The mere fact that you're asking this question indicates that you're probably not suitably qualified to handle this for others. Why not have someone qualified handle this?