I have an idea for a story, but I know I wouldn’t be able to do a good job of this. If anyone wants to give this a shot feel free to start writing it.
Emma had twins and Regina adopts both. One she names Henry, and the other she names Daniel. Henry is pretty much the same as he is in canon, but Daniel is firmly loyal to Regina. To Daniel, it doesn’t matter if she is the Evil Queen or not; she is his mother and he knows she loves him, so his loyalty to Regina is absolute. He doesn’t blame Emma for giving him up, he is happy with his life and family in Storybrooke. However, has no fondness for Emma and wishes she would leave.
Regina is hurt by Henry’s constant rejection, but she is happy to have one person who loves her in Daniel.
Basically, the story would show how canon would have been different if Regina did have a son’s love.
* Regina is not as cruel and bitter in Storybrooke as she was on the show. Since she has Daniel she doesn’t ever feel alone. She still has a mean steak to people she dislikes, but she has mellowed a bit.
* Daniel (the kid) is NOT a reincarnation of Regina’s true love.
* Daniel doesn’t know if the curse is real or not, but either way he doesn’t really care. It wouldn’t change anything for him.
* Regina loves both of her sons with all her heart, and Henry’s bitterness really hurts her. Luckily, Daniel is always there to comfort his mother.
* Daniel doesn’t want anything to do with Emma, which makes their interactions particularly painful for Emma.
* You can show the conflict between the two boys; Daniel firmly on Regina’s side and Henry firmly on Emma’s. A rift is definitely growing between the once close brothers.
Kinda late responding to this, but I’m working on a fic right now that sort of touches on this. It doesn’t follow this particular storyline, but it does put a horror twist on the idea of Henry not being Regina’s only child.