The Haunting of Hill House Season 1 Episode 9
After the storm, Olivia talks to Mrs. Dudley and tells a story from her childhood that involved her being unable to grieve her father's death.
Later, Olivia is reading when she gets a terrible headache. She goes to get some medicine and when she returns she is in Shirley's morgue and she sees Nell's and Luke's adult dead bodies. She mentions the vision to Hugh later but he thinks she is just stressed out.
That night she encounters Poppy Hill in her reading room and they talk about their fears of losing a child.
After another talk with Hugh, Olivia speeds up her timeline to leave to see Aunt Janet. However, she lies to Hugh and doesn't end up going to her sisters and instead returns late at night.
She wakes Nell and Luke to have a tea party and also invites Luke's friend Abigail who is spending the night. They enter the red room and Olivia pours them all a cup of tea.
Shirley wakes Hugh after running into Olivia and he realizes that Olivia has spiked the children's tea with rat poison. He arrives at the red room a minute too late, as Abigail has drunk the tea and dies.
Hugh knocks Olivia into a wall, which leaves her incapacitated for a few minutes, while he gathers up the children to leave.
While left alone, Olivia talks to Poppy and laments that she just wants to wake up before falling to her death.