This is ...

This is the festival day for children who are aged seven, five and three. three year and five year old boys,
three year and seven year old girls are cerebrated on their growth at a shrine as an annual event on 15th November in Japan.
The Kanto area originally used to have it as a local custom,
and the Kyoto-Osaka area used to have jyuusann-mairi (the festival day for children who are aged thirteen years old) as correspondence.
However, nowadays, those customs have been spread out into many local areas in Japan.
By modern Japan, Japan used to be a developing country and struggle from poverty, shortages of knowledge on health and nutrition.
Due to that, the survival rate for babies were extremely low at that time so that people cerebrated their survival as a turning point
and it is now well-established event.
Why boys are cerebrated earlier than girls is that the survival rate for boys was lower than girl’s one
and may be a meaning of a successor.

Ceremony of Kamioki
For three year old boys and girls. It is hope to be good in health.

Ceremony of Hakamagi
For five year old boys as boys, Not young children anymore. It is the first time to wear Hakama in kimono.

Ceremony of Hakamagi
For seven year old girls. It is the first time to remove a tsuke-himo, then put an obi.