In future versions of The World That Became, it is possible for the Protagonist and their romantic interest to have children that will be unlockable as party members after they have been summoned from the future at Wend's Shrine.
After the Protagonist has entered a romantic relationship with a party member, it is possible to summon their child at Wend's Shrine. The child will then join the player's party. Each character that can be romanced by a Protagonist of opposite gender has a specific child tied to them. There are also two children exclusive for male-male and female-female relationships through adoption.
A child that is not adopted inherits the skin tone and eye color of their mother and hair color of their father. They are also of a class other than the one of the parent that is not the Protagonist. In addition, all children inherit a skill from the Protagonist depending on the Protagonist's class and level.