Is investing with family inheritance a good idea?

[Kyle Cross]

I am a 23 year old who recently graduated from college with a business degree focusing on real estate finance and development. I have been working the last 6 months as a commercial real estate agent focusing on retail investment sales in Los Angeles. I am on commission only compensation, so I moved back in with my parents, and am trading all of my time (60-70 hour work weeks) for little/no money. 

My goal is to move more onto the ownership/management side of the real estate industry as soon as possible, but am not sure the best way to go about making the switch. I know a lot about the industry through my education, but have very little/no practical experience when it comes to managing investment properties. 

There are 2 fourplex properties that my grandparents owned outright and recently passed on to my parents, who don't know much at all about real estate investing or growing the investments. The current portfolio doesn't require much management, but I feel there is opportunity to grow the portfolio moving forwards. I believe they will let me assist them with managing and helping grow the investments, but am worried about making any moves since I have no direct investment experience of my own. 

I know investing with family can possibly hurt relationships if things don't go well, so I don't want to make any big mistakes since this is a large amount of my parents inheritance. Any suggestions on the best ways to make the switch to becoming a full time investor and help grow my family's (and my own) portfolio?