However, the movie reveals that Sister Irene and Lorraine Warren are from the same bloodline. This was revealed when the movie explored Sister Irene's heritage, and it showed she is a descendant of Saint Lucy. She then has visions of people in Saint Lucy's bloodline, and one of those people was Lorraine Warren.

The Nun movies are actually prequels to The Conjuring series. While The Nun and its sequel take part in the 1950s, The Conjuring is set in the 1970s. Valak torments a young nun throughout the series, and it's only when Lorraine encounters Valak two decades after that we see the demon defeated.