One manager taking over for another is expected to cover the same territory—leadership, strategy, manufacturing merchandising, acquisitions. But each can be done in varying ways. And in the case of a family business, you are more likely to succeed by deploying your unique talents than trying to emulate those of your parents, especially as a company and its business environment changes from generation to generation.  Succession plans are vital for any institution but especially those led by iconic figures. But a succession plan is less likely to succeed if a company's prosperity is due primarily to a leader's personality traits. And many people attribute Berkshire's success primarily to Warren's peculiar tastes, including Berkshire Hathaway Vice Chairman Charlie Munger in his postscript to Buffett's recent letter.  However, Berkshire culture runs far deeper and broader than a single personality, defined by a core set of common values that stretch across the company's 350,000 employees. Far from a one-man show run from a central corporate office staff of 25, Warren's greatest achievement has been building an institution larger than himself. Berkshire's scores of companies tend to share management principles such as thrift, integrity, trust and a sense of permanence. Maintaining this culture will be Howard's job, one far easier than carrying out the jobs his dad did, which is better left to a group of experienced professionals.  Read MoreThe No. 1 way to destroy private company wealth  Many children have learned to avoid the trap of following in parental footsteps, and it's something the rest of us can heed as well, whether children of legend or not. Compare the twin children of legendary British Prime Minister Margaret Thatcher, Carol and Mark. While Mark tried but failed to mirror his mother in national politics, Carol never ran for public office. She first moved to Australia to make a name for herself in journalism, before returning to Britain to cement her leadership role in that profession. Chelsea Clinton may yet enter her family business of politics but has thus far moved through other fields—business consulting, hedge funds, journalism and, most recently, nonprofit work.  Some may still judge the children of legend by the outsized standards of their parents. But tempting as it can be to struggle to measure up—or to become a recluse—it is best to forge ahead on your own path and to walk in shoes made just for you.  —By Lawrence A. Cunningham, author of "Berkshire Beyond Buffett: The Enduring Value of Values" and Henry St. George Tucker professor at George Washington University
In family business succession planning, the biggest mistake is assuming a child is the right person for the job. They often aren't.