I really don’t think Regina is Rumple’s daughter. I think they want us to think that, but it would make everything FAR TOO complicated. Henry Jr’s adopted mother (Regina) would also be his father’s half sister, making them cousins.
I think maybe Rumple and Cora did have an intimate relationship, but it wasn’t love, I think it was a power maneuver. Cora seduced him, got him to trust her, and then tricked him with the dagger. With regards to Rumple being Regina’s father, I think it’s a reminder that Cora won in the baby Regina battle. Cora calls her “MY daughter” like a reminder that she got out of her deal with Rumple for baby Regina.
[adrotate group="5"]
"He was a lot of things to me" "The only conclusion was love"