The public second half of a changeling wedding, held a month later with guests, food, gifts and singing.
The Confirmation is the second part of a Changeling marriage, scheduled roughly a month after The Small Wedding. Mordecai explains in chat that changeling couples traditionally need a full month to decide whether they are actually compatible - most of their marriages being arranged - so the small wedding includes signing Divorce Papers that expire if unfiled. During that month Louis and Juice Box are legally married, but either can file and annul it without consequence.
The Confirmation itself is the big, familiar celebration: guests, food, gifts and singing, and the moment when the couple repeats aloud the vows they whispered privately. Princess Donut scoffs that a month seems impossibly far away and is immediately in chat loudly preparing for the party, having been denied her rings and her singing at the first ceremony.
The traditional public wedding a month out, and Donut's new party-planning obsession.