I know it sounds weird but i think Gigi is Grace's mother. She never seems to want to hurt her,she seems to care about her more than the other girls and wants to be her stepmother. She may have done things to changed her look which is why Wes didnt recognise her. As for the show i believe that things will contradict the past and present and many future scenes will not make sense. As for the bath tub baby, i think it may be a half sister to Grace and maybe that is why the attacks started when Grace arrived and the red devil tried to saw off her fathers arm.