I’m trying to remember the title of a movie I saw on tv in 2016-2017.  What I remember is vague bits of plot at best so am at a total loss.

the movie is about an old woman, I think she is an author and either a journalist or another author has gone to her house to interview her about a book she wrote or to help her finish a book.

the old woman tells a story about her childhood (I think). I believe there are 2 sisters or 2 siblings, possibly with red hair, I have an image in my head of red headed girls in white dresses.

I would describe the setting as kind of southern gothic, big house kind of creepy, you think maybe it’s going to be scary but it isn’t.

i also remember something about a gardener, someone being pushed off something and possibly a fire (super helpful I know)

in the end it is revealed that there was an additional sister who no one knew was related to them.

The girls may have been vying for the affections of the same young man.

I am not even sure if all the details are accurate, but I have flashes of the described above running through my brain