After receiving the news of Nell’s suicide, Shirley insists on preparing her sister’s body herself.
In a flashback, young Luke catches a glimpse of a mysterious young girl in the distance at Hill House.
At her mother’s funeral, Shirley is terrified of seeing her deceased mother. However, the mortician "fixes" Olivia to look peaceful, which inspires Shirley’s future career path. Present Timeline:
Young Shirley finds a litter of stray kittens. Despite her efforts to save them, they all die. This trauma, combined with the "broken" appearance of her mother’s body later, drives her obsession with "fixing" things.
Like other siblings' specific rooms, Shirley’s "Red Room" (her office/workplace in the house) contains subtle red elements, a recurring motif throughout the series. Open Casket | The Haunting of Bly Manor Wiki | Fandom
While Shirley tries to maintain a facade of perfection and control, her world is constantly undermined by the repressed horrors of Hill House and the messiness of her family’s shared grief. Key Details & Trivia
Shirley now owns a funeral home with her husband, Kevin. She is a perfectionist who views her work as a way to provide families with a "better picture" to replace scary memories of death.
Shirley is often interpreted as representing Anger in the five stages of grief. Her anger manifests as a need for control and a literal "fixing" of the dead to mask the chaos of loss.