Lucille was Isabella Marshall's daughter from an earlier relationship. William Lancaster was her stepfather, but their marriage did not last, as Isabella soon found her husband controlling and had to seal his essence inside a painting to be free from him. Decades later, William's essence was accidentally released and Lucille became a target in his restoration. She was saved by the Charmed Ones in the end. Lucille doesn't know the Halliwells are witches, but knows they are something special.