Ticket counts arrive by email and suddenly everyone is doing math about who sat where in 2018. Graduation is your child's finish line. It does not have to become a referendum on the divorce.
Ask the school how tickets work. Split them fairly if seats are tight. Put the plan in writing. Decide photo moments before anyone is crying in a polyester gown in a hot parking lot.
Parties are not loyalty tests. One joint gathering works for some families. Separate ones work for others. Both can be kind. Ask the graduate what feels good, then set adult limits so they are not managing your feelings between cake and speeches.
Gifts and money talk stay in a private adult channel. Do not compete in front of them. Coordinate duplicates only if your kid cares.
Assign jobs if emotions run hot. Flowers. Dinner reservation. Ride to the venue. Clear jobs reduce collision at the curb.
Ceremony behavior stays quiet. This is not the day for a speech about the past. Years from now they will remember whether they felt free to enjoy it. Help them feel free.