November 15th is the day of the Seven-five-three festival in Japan. This is a traditional Japanese event to celebrate children's growth and pray for their future health and well-being. This traditional passed to the samurai class who added a number of rituals. Seven,five, or three year-old children are beautifully dressed in traditional Japanese kimono and taken to a shrine. http://www.inage-sengenjinja.or.jp/index.html
I would like to explain why "Seven-five-three ".
Children who up until the age of three were required by custom to have shave heads were allowed to grow out their hair.
Boys of age five could wear hakama for the first time.
Girls of age seven replaced the simple cords they used to tie their kimono with the traditional obi.