A person who put a cap on a young man's head at this ceremony was his guardian called 'kanmuri-oya' (literally, "cap parent"), and during the early-modern times, an emperor's kanmuri-oya was selected from the heads of Gosekke (five top Fujiwara families whose members were eligible for the positions of Sessho [regency] and Kanpaku [chancellor]).
この時、若者に冠をかぶせるのが「冠親」と呼ばれる後見人であり、近世において天皇の冠親は五摂家のうちどこかの当主が担当していた。