Mal's long-lost little sister

Livvy (Olivia) has always felt different then the rest of her family. She has long blonde hair that, fades to purple about halfway down and no matter how hard they try, no one can get rid of it, cutting it the purple somehow magickly back, dying it the purple stays, they've even tried to let grow out and that doesn't work. They just give up on trying to get rid of the purple, until a purple haired girl from the Isle Of The Lost who can do magic, shows up and changes girls hair, Audrey asks if she would change Livvy's hair, she tries but the purple is still there. Read to find out why.