What do the merpeople call their Island?
And how long has Helena been queen? is she Queen of the whole merworld, or just the island?
I'm assuming she is the only ruler, as the merpeople are peaceful there is no reason nobles/royals/people would fight over titles, land, or resources. So it would be one united kingdom?
Since its a monarchy she would have gained her position after the last king/queen died, and she would have most likely been princess before hand, what was the rumors among the merworld about her absence/missing. (when she was gone during her time as a slave I mean. Since no one knows.)
And how did she escape and come back to the island/ocean?