Name of cartoon show

[Xana]

Hi, i need your help finding the name of a certain cartoon show. I remember that one of the characters, i think the main one, did some mistake that turned him into a skeleton like person with the ability to walk into a shadow and appering some other place, and i thing his sister, a red-haired character gained the ability to fly. There was another character affected by the first one's mistake, but i don't recall what happened to him...
Can anyone help me? Remember the name of the show??