WARNING: The following contains SPOILERS for Insidious: The Red Door. The final film of the Insidious franchise, Insidious: The Red Door, hit theaters and audiences immediately noticed that Barbara Hershey's character Lorraine Lambert wasn't in it. The Red Door closed the book on the haunting Lambert family saga once and for all. Their story began all the way back in 2010 when, in Insidious, Josh Lambert (Patrick Wilson) and his wife,, Renai, (Rose Byrne) saw their son, Dalton (Ty Simpkins), fall into a coma after astral projecting and wandering too far into a spiritual realm known as the Further. Insidious 2 continues the Lamberts' story, though this time it's Josh who needs saving.

https://screenrant.com/insidious-red-door-lorraine-lambert-death/