My daughter wants to miss a swim gala she agreed to. How much does she owe her relay team?

My twelve-year-old put the art workshop leaflet beside her goggles and said, "I want to do this on Sunday instead." The swim gala is that morning. Two weeks ago, she told her coach she'd swim in the relay.

She likes training and says she isn't asking to quit. This workshop is a one-off with a friend who doesn't swim. I had already paid her $35 gala entry, and my first answer was, "You made a commitment." She said I usually confirm events in the parent chat before asking her, which is also true. This time, though, I heard her tell the coach yes.

The coach says another swimmer could take her place if we give notice by Friday. He'd rather she attend because the relay group has practised together. Her teammates have been talking about matching caps, so this isn't just a calendar entry to them.

I don't want every inconvenient commitment to become optional. I also don't want an activity she enjoys to take every weekend by default. Should I hold her to this gala, let her withdraw while a replacement is possible, or ask her to speak to the coach before deciding? How would you distinguish a child's own promise from the sporting schedule a parent has built around them?