Who's that girl behind the curtain?

My daughter played the Wicked Witch of the West in her school's musical production of Over the Rainbow. They did it with two separate casts and two separate showings but the children all learned the parts together. It was a great experience for my little actress, she made quite a few new friends, she became especially close with the girl who had her sister part in the other production.
My daughter's performance was first and it went off without a hitch. We are all very proud, and she got her very first bunch of roses after her showing. The second showing didn't go as well, the second Witch had trouble with her song. Now in an elementary school production, you don't expect the actors to be able to sing, it's just kind of a bonus if they can, you do expect however, for them to try and learn the words to the songs. When it came down to it, the other Witch couldn't do either. She asked for my daughter's help during her song. At first, she was supposed to stand next to her and they were supposed to sing the song together, but the second witch decided she wasn't thrilled to have the first witch in her limelight. Eventually what was decided was that my daughter would hide behind the curtain with a microphone and sing while the second witch mouthed the words. This did not work exactly well. Because it's such a small stage, and an informal folding-chair set up, half of the audience could see my daughter and there were grumblings all over the place. By the time the song was over my daughter could see tears rolling down the cheeks of the other girl.
It broke my little witch's heart, and to make matters worse she had to face the ridicule of the rest of the cast, in fact, the 'Dorothy' accused her of trying to steal the other girl's fame, as she put it. This all happened last night and I have no idea what she is facing in school today as I write this, I hope that it's not too bad for either of the witches.
This situation has given me a new understanding however, of why some people try to be less than they are in order to gain acceptance from others. Hopefully, as one of a set of two very supportive parents we can help our daughter to work through it.