This boy's robe dates from a era when young boys in Europe wore garments with skirts, a custom with unclear origins, but which most likely had to do with making it easier for them to urinate. The style was common until about 1920. A boy usually received his first breeches or trousers between four and seven years of age, sometimes in a special ceremony held by the family.
You are all set!
Your first Culture Weekly will arrive this week.