…has possessed her sister for years

Hey!

I’m looking for the title of a thriller/horror movie where, I believe, the main character is a writer who visits this once-prestigious manor (that used to be a hotel?) because she wants to restore its glory, so she rents a room for the while she’s doing her research. The movie opens with her driving up through the grounds. The man helping her at the front desk is the son of the family who used to run the place.  He tells her not to go into certain rooms. His mother lives in her own quarters, which are off limits, and all she does is sit in a chair and stare out the window, unresponsive. She doesn’t talk and doesn’t respond to stimuli, but she’s alive. I think she comes out the trance sometimes…

Basically, we find out that when she was young, her sister died in a fire or she drowned?, and then started haunting the manor – thus shutting down business. And the ghost is keeping her sister (the mother) under her grasp and I guess is kind of possessing her? I think the ghost sister was an evil child.

The ghost girl tries to kill the lead character several times…the movie ends with a fire at the end and the thought-to-be-creepy grounds keeper ends up saving the main character. I can’t remember if the mother dies or not, or if she comes out of the trance.

This was an American movie released sometime between 2000 and 2010. I remember renting it from the Rogers video when movie rentals were still a thing. The cast wasn’t super A-list.

Thanks for all and any help!