That makes no sense. For one thing for it to be a credible accusation, since Natalie is dead and cant confirm or deny it, her daughter would need to have in her possession, some sort of proof, like a hand written letter or audio recording of her mother naming her rapist. And if she does have that, why wait until the rapist is dead? They dead cant lie, but they also cant defend themselves either.
Lana Wood is her sister, not her daughter. She would know.