As a parent, I don't know about Pussy Willow. It would catch my eye instantly, but not how you probably meant it to
. I think the moment I'd see the title I would be... "wtf? is this for real?" - but that's just because my mind is dirty
for a firefly story, I would think of something along the lines of them gathering together to make sort of a beacon for something, whereas just one firefly wouldn't give enough light. Sort of a story of how if people come together they can do great stuff. Applied to fireflies.