Eighteen? Nineteen? While gross, it's not incest if she's his STEP-granddaughter.
Well, like others on here, let’s see what the facts prove out. Meanwhile, considering that teen means 13, 14, 15, 16, 17, 18 and 19, why do you assume it was only 18 or 19. And, I don’t care if she was 20, it is STILL gross. Blood is not the only thing that matters here - relationships matter and when you grow up with your “grandpa,” and he violates the sacredness of that relationship, something is just gross. I bet you thought Woody Allen’s relationship with his step-daughter was wrong. There is no difference.
Oops - I mean Woody’s adopted daughter. She was not a blood relative either.