My cousin or more like brother as we were raised in the same households has a child which is about to turn 3 next month. He and his partner invited us to his child's party which is on the Saturday which is great as me and my partner work weekdays but now the child's mother has posted saying his "proper party" is on Monday when no family members can come because of work schedules. AIBU to be upset that I'm not invited to her proper party?