Victor's daughter was the child of Victor and his wife. Once she was born, he considered his life perfect. When a vampire entered the village it was Victor's love for his family that made him so desirable to her so she set about making him undead. After this, the woman took Victor's wife and child away from him.
Victor always carried a locket with an image of his maker to remind him of his family. The place in the church graveyard where Olive Hawthorne discovered Victor feasting on a deer in the 20th century was the grave of his wife and child and his memories of their deaths still visibly shook him when he spoke of it. (HOMEVID: White Witch of Devil's End)