In Japanese numerology, odd numbers are lucky. Each year, on the 15th of November (luckiest day of the year), the Shichi-go-san (7-5-3) festival is held to celebrate children coming of age. The festival dates to the Heian Period (794-1185) when nobility celebrated their children entering middle childhood. By the Edo period (1603-1867), this practice spread to commoners, who began visiting shrines to have prayers offered by priests. Minor changes in Shichi-go-san were also introduced during Meiji period (1868-1912).Until the age of three all children had their heads shaven, but after three, they could grow their hair.
Three years old girls wear hifu which is kind of vest.
At the age of five, boys wear haori jackets and hakama trousers (traditional Japanese clothing) for the first time.
Girls started using obi with their kimonos when they turned seven, for their Shichi-go-san visit.
The young girls wear wooden Okobo getas (also called pokkuri and koppori), made from blocks of willow wood with a small bell inside a cavity in the thick sole. The lacquered okobo are held to the foot by simple thong-like straps.
Afterward, the ceremony children are photographed with their families and children receive long red-and-white sticks of hard candy called chitose-ame (thousand-years candy). Whoever eats the candy will have a thousand years of happiness. Turtles and cranes—symbols of long life—decorate the candy bag. The candy and the bag are both expressions of parents' wish that their children lead long, prosperous lives. Later, the children have a special dinner to celebrate. November 15. One of the most popular Shichi-go-san destinations in Tokyo is Hie Shrine in Akasaka. It has been frequented by many families celebrating Shichi-go-san since the Edo period, and today it is visited by around 2,000 families every year.