I think what I want to know is: When Hunter and Drew left (after David confronted them), did they cut ALL contact with the family?
That's how I imagined it happening. So how would Ophelia be able to tell Hunter anything?
My theory?
Hunter and Drew spend years travelling the world, visiting various doctors that help Drew transition from him to her.
Also during this time, Hunter and Drew perfect their techniques for seducing women.
Drew uses psychology and her(new)appearance, while Hunter uses pharmaceuticals and his...grandfatherly charm?
At some point, Hunter realizes his time is running out, so he begins his plan to impregnate Ophelia by having Drew seduce David.
During their affair, Drew does something that leads to David's death.
And like magic, Hunter appears at Ophelia's door to console his grieving daughter.