The Charming Daughter of Mr. Gold

No one knew that Snow White was going to have twins except for one person, Rumpelstiltskin. He knew and told the Charmings about the twin, but think that it was some sort of lie or trick refused to believe him, until the day that her and Emma were born. Now little Mia is in Storybrooke with Mr. Gold, so much mystery surrounds her, so how will her being there effect the town?