What's the movie with the old lady with a trunk filled with her dead sisters things?

so, I can't remember the movie for the life of me. But, it's an older
movie with this girl who is interested in paranormal stuff and so she
explores haunted houses and everything and she is friends with this
old lady who said her sister died in like a fire or something but,
really the old lady killed her sister and she has a trunk filled with
her dead sisters things like her doll and I think her sister might of
been a spin off of Shirley Temple or something like that. lol