They see everything already recorded
Every custody entry, cost and request made before they joined is in the shared record, attributed to the person who made it. Nothing is hidden from one parent and shown to the other. If your household is on the free plan, the same visibility window applies to both of you.
Requests waiting for them
Requests you made before they joined are waiting in their Requests list, and they answer them the normal way. The notice on each one is still counted from when you made it. Their Overview page lists what's waiting for their first two weeks.
They weren't notified about those earlier requests when you made them, because they weren't a member yet. Notifications start from the moment they join.
The record shows when you paired
History shows when they joined. In reports and exports, any period before that is labelled “Household not yet paired: entries in this period were recorded by one parent.”
Links you shared stop working
If you shared requests before they joined, those links close as soon as the household is paired. The requests themselves are now in the app for both of you.
Leaving later
Either parent can ask to leave the household. This is currently handled by our team. See Delete my account or leave the household.