The successive head of the family or the successors to the family created fictitious relationships to emperors and retired emperors of each era, by being adopted as their children, then they were able to receive title of Imperial Prince by the Imperial Order which secured their position to succeed to the Imperial throne.
歴代の当主・継嗣は、そのときどきの天皇または上皇の猶子となることによって擬制的な親子関係を構築し、そのことを根拠にして親王宣下により親王の地位と称号を与えられて、皇位継承権を保障されてきたのである。