It is a little bit of a tired trope, but I've never written anything 'typical' before, so I thought it could be fun to put my own spin on it. I was also thinking trans!swan sibling as well (which would add another layer to the 'breaking traditions/family legacy' themes of the show.
Plus it'd also give me something to write in the once upon a time universe when I'm not working on Evermore - which is more original plot than canon. Make my brain have a rest from planning. Glad you're interested!