Chiyūri

Chiyūri [七物命; ちゆうり] is a traditional Kantonese festival held by a couple seven days after a baby is born. Typically all members of the family are expected to be present, as it is a very important event during which the infant's name is revealed.
Chiyūri will typically begin in the evening, after everyone has spent some time socialising and catching up. The parents will often make a point of giving each family member the chance to hold their baby, as this is considered auspicious. Both the parents and child will be wearing white, to symbolise purity and fortune. It is customary for each guest to leave a token gift, such as money, food, or baby supplies as a gesture of support and generosity.
At dinnertime, everyone congregates in either the kitchen or living room and the baby's name is revealed, written on a piece of card which is often decorated with pictures of the child and attractive designs. Sometimes, according to the parents' taste, these cards can be more formal-looking, to emphasise the importance of the event. Other items dedicated to the infant may be presented, such as a stamp of their handprint or a small stone with their new name painted on it. This stone is thought to symbolise longevity and lack of need. After the name reveal a large meal will be served, and glasses of gizan are handed out. 
It is thought that Chiyūri was originally celebrated to mark the week-long survival of a newborn in times when infant mortality was very high. A similar event called Chijōri was traditionally held to celebrate an infant turning seven months old, another milestone in their short life; however, it is less popular and well-known nowadays compared to Chiyūri.