Goodbye, little sister

What if there was a fourth sister of the Witches? This Sanderson was loved by her three sisters, even if she was a good witch, but greediness of youth clouded the three's mind. As they were being burned on the stake, the three witches put a spell onto the youngest sister. No one remembers the fourth as the years go by. What happens when three teenagers and a child wake up the witches, and they don't want the child, but also the girl that looks familiar.