There exists not a clear set of guidelines regarding the age at which an individual becomes a junior idol: Yumi Adachi, for instance, started her modeling career at age two and many other idols have starred in image DVDs at the ages of three, four and five.
Yumi Matsutoya | Yumi Yoshimura | Yumi Stynes | Mitsuru Adachi | Yumi Ohka | Yumi Adachi | Kaoru Yumi | Adachi-ga Hara | Adachi District, Fukushima | Adachi clan |