Big but nice looking girl and the dress is nice.
Yes, she's a cute kid. Good grades, too.
Most likely just a nice kid, and there's a lot of other nice kids around,just like her.
She didn't need to be told the night before her prom that she couldn't wear the dress. A week before at least gives her a chance to do something else. Her date had a tux, flowers and dinner reserved, I'll bet.
Kids will almost always accept an adult's decision, even if they don't like it, if they are fair and they are subjectively explained. I don't think this decision by that principal met those parameters.
longjack