Winchester (2018) on Netflix

Plot summary

Sarah Winchester, widow of the gun manufacturer William Wirt Winchester, lives in a mansion in San Jose, California that has been under construction for years. After the deaths of her husband and their child Annie, she is convinced that Winchester rifles have cursed her, and that the souls of the people killed by those guns walk in her house. Her niece Marion Marriott and Marion's son Henry live with her, and at night a mysterious entity possesses the boy. The Winchester company, doubting Sarah is fit to run it, hires Dr. Eric Price, who mourns his wife Ruby and depends on drugs, to stay at the house and assess her mental state.