One of the key components of the Insidious franchise has been the theme of family. It's evident in the main timeline with Josh (Patrick Wilson) and the Lambert clan. But it's also quite apparent in Insidious: Chapter 3 and The Last Key, which had other families uniting and battling demons from the Further.
Source：https://www.cbr.com/insidious-5-ben-burton-horror-trope/
