The Innocents
Deborah Kerr stars in this 1961 cult classic. Kerr is tasked with caring for two children in a haunted mansion. This movie has serious The Shining vibes from even before that movie was conceived. If you want to watch a more modernized version of this classic, check out The Others, it's a film from 2001 that serves as a remake with a bit of a twist.
A Tale of Two Sisters
This 2003 fright-fest is about a sibling duo who are growing up together in South Korea. They live normal lives outside of the fact that they've been getting haunted by a terrible poltergeist that's controlling everything they do. Or, are they making all of it up? You'll have to give it a watch to figure that out.