Princess who love to sing

Princess Isabel loved to sing very much. She sang anytime and anywhere. When she was singing, everyone must be quiet. If not, she would punish them.
One day an old beggar asked her some money while she was singing. Princess Isabel was very angry,but the old beggar was angry too. The old beggar was actually a witch. She cursed Isabel,"from now on, you cannot sing!"
fortunately, there was a fairy. She was good one. She said,"you can sing again after you do a good thing to someone else".
From then on, Isabel was always good to everybody. She wanted her voice back. So, she travelled from one city to another to do good things.
One day, when she took a rest in a forest after her long journey, she saw a thin little boy. The boy was hungry. Without thinking of herself, Isabel gave her only sandwich. Sudenly, she sang. The beautiful voice was back.