Help finding the story...

I came across a story long ago in which due to some kind of punishment two friends have to attend a prom as a punishment.
The one who has to o as a girl whines a lot about being him as the girl of the two and the other of course as a boy. The mother of the "girl" assures "her" that this is also a punishment for "her" friend as he has to endure the embarrassment if it was found out that he has attended the prom with a boy and not a girl. Thanks in advance.