I did a few sketches of Jun a long time ago, back when I got Kelly's hair wrong. But I thought she was much younger than how you draw her, like a little kid. I'll try and figure out a way to post them so that you could see em. They're kinda silly,

As for finding hairstyles for Jun, I usually flip through magazines to see what the people in ads look like. If I find something I like the look off, I try and draw it out. I like looking at the hair product ads like gel or shampoo since they show alot of hair. ^^

But Jin's a guy and has short hair, Kelly's hair is longer but still short, you might want to make Jun's hair a bit longer to set her apart from her siblings. Unless you make them alike and they all have short hair. eh...i guess that's not helping...>_< But it's up to you really, once you find a style that works and you're happy about, everthing else will fall in place.

Ah, and very cool montage of emotions! She kinda looks like Tira when she has the ponytail!