Helena Ravenclaw is the child of Rowena Ravenclaw (a founder of Hogwarts). She is known as the Grey Lady and is the ghost of Ravenclaw. Rowena asked the Bloody Baron to find her but was killed by him.

Harry Potter...
Don't be a Dursley to one house, character, family, etc.
They all have their own "good" sides (Narcissa Malfoy, for example).

BE KIND!!!!!