Haunted player who doesn't know it yet.....

[Delta7]

I had the idea to have one of my players haunted by the ghost of Elara from Falcon's Hollow. However, I don't want the player to know what's happening. I want only her character to be able to see her and receive hints as what to do from time to time, but without the other players realizing that this is happening. Eventually, her restless spirit will be less helpful and more disruptive and possibly even dangerous forcing them to seek out an exorcism. Any ideas how I can do this? We will mostly be using Roll20 and I had just planned on muting my microphone and calling the player who is haunted with the sighting if/when I needed to.

Thanks in advance for any ideas!

[KenderKin]

You could start with dream hauntings, that is visions that you describe to the player at first and then move up to something like the oracle's haunted curse.....