For these reasons, the eldest son is commonly the beneficiary, however, if succession is by an individual without blood ties to the family, it is common for such unrelated successors to be required to become a member of the family (eg. by marrying into his wife's family and assuming their name etc).
そのため、長子相続が一般的であり、血縁外の者が継ぐ場合は一般的には一族の中に入ることが求められる（婿養子になるなど）。