Marriage and having children are not established features in the current Witchbrook material. The relationship system that has been explained goes through dating and going steady, with sleepovers among the privileges of commitment. That is enough to describe a romance, but it does not supply a wedding or child-raising system.
If starting a family is the part of a life sim you most want, the available relationship details do not yet resolve that requirement.
The announced relationship before commitment
Witchbrook has eleven romanceable covenmates. You develop a relationship through contact, gifts and dates, with each character becoming ready at a different point in their story. You can also follow their story through friendship without dating.
The next disclosed commitment is going steady. A family system is not part of the progression explained so far.
Going steady is the announced commitment milestone
The post office has separate categories for Dating Cards, Go Steady Cards and Breakup Cards. Once a relationship has developed through successful dates, gifts and regular contact, a going-steady card expresses a further commitment.
Sleepovers are explicitly associated with that stage. They should be understood as a privilege of the steady relationship: the announcement does not call them marriage or describe them as establishing a permanent joint household.
The three disclosed card categories express relationship changes.
In multiplayer, players may compete for the same covenmate until one goes steady, and the TGS developer interview describes one committed partner per candidate. That rule concerns the dating commitment; it does not announce marriage between players or marriage ceremonies for NPC couples.
A wedding in the card-origin story is different evidence
The dating material includes a story about an old mayor who sent affection cards for almost any occasion. The accompanying wedding reference belongs to that fictional history of Mossport's card-giving tradition.
It explains the setting's joke and why the post office is involved in romance. It is not a demonstration of the player choosing a wedding date, buying a ring or unlocking spouse events.
There are similar reasons to keep housing and family questions separate. You inherit a cottage from your aunt, and online friends can receive smaller cottages of their own. Those housing systems have practical and decorative uses, but they do not establish homes for children or a marriage-based house upgrade.
Graduation and a longer life in Mossport
Graduation does not end all announced activity: you can continue postgraduate learning, improve earlier grades, complete knowledge and develop your business. Those continuing goals describe what you can keep doing with the life already built in town.
They do not describe ageing into parenthood or passing progress to another generation. For romance, the disclosed milestone remains going steady and its privileges. For marriage and raising children, there is no established procedure to guide you through yet.