Answer:
Charlotte has the priority to claim Autumn as her dependent even though William covered 70% of her living expenses during the year. In order for a parent to be able to claim a child as a dependent, he/she must live with the child for more than half the year. In this case, since William left the house, Charlotte has preference over claiming Autumn as her dependent (even though William lived with Autumn for 10 months). Also, a parent always has priority over other relatives including a grandparent.