I could never have done the witch’s tasks without the help of the white dove. When she lit on my shoulder, I caressed her white feathers and kissed her little red beak. In that moment, a beautiful young woman stood before me. My kiss had freed her from the witch’s power, and now she was resolved to free us both.
She tied herself to me with a red silk thread, and assured me that I would know her, by that thread, in any form she appeared.
Prince Enslaved by a Witch in The White Dove, Pink Fairy Book