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branch family; cadet family; establishing a branch family
江戸時代、三男が分家した。
During the Edo period, the third son established a branch family.
毎年、本家と分家が一堂に会する。
Every year, the main family and branch families gather in one place.
その古い家系図には、本家と分家が詳細に記されている。
The old family tree meticulously records both the main family and its branch families.