Jigoku Shoujo Futakomori EP18 - That Person's Memories

A girl comes home from work one day to find her mother, who went away when she was still young, has returned. Not only that, but her father wants her to have to pamper her mother every day, causing problems for the girl. She uses the Hell Hotline to get try to get rid of her mother, and tries to do so eventually, but finds that she cannot, because her father used the Hell Hotline and therefore got the straw doll she had. She rushes over to where her father is taking her mother for a walk, but finds her father has already sent her mother to Hell. He father tells her the truth: she is not the daughter of the woman she thought was her mother. After discovering his wife was infertile, her father had a her with another woman. This caused his wife to get angry, and eventually she got involved in a car accident to try and kill herself. The girl then remembers that her mother did accept her once, but knows it is too late.