Sora means Sky, Kairi means Sea, Yasi is the name given to a cyclone, which is where Wind and Water meet. So yes, Yasi looks like a brown-haired Kairi from when she was little, her brother Aero (Fitting name) is three years older and looks exactly like his dad (Sora). Like Mivii explains, he doesn't grow much, in DS Yasi is actually taller than him XD Zone (Name having to do with space, which reffers to darkness), is Riku's son (Looks like a little Riku) and the girl with glasses and flippy-ended silver hair is Midnight, who is his sister and 13 at this point within the series/story.
Mivii, has two tiny nostrils (Which she couldn't see) and all she has for her ears are tiny holes on the sides of her head. Other-wise yes, her face is soft-peach and smooth.
Then, read and learn my dear reader 
Chapter 4 - Identity
I cried myself to sleep that night, I didn't tell Yasi, I was too afraid of what her reaction would be. When she came to the island two days later I told her I didn't want to take my hood off. It didn't seem to affect her, though she did tilt her head at my sudden out-burst. 3 months passed by, I don't think Yasi ever told her brother or the other two about me, I hope at the very least. I've finally overcome pronoucing 'R'(s), just something random to say.
Mivii seems to really be a meaningless name, somewhere along the way I asked her if there was any other reason to her giving me the name. Yasi, in return asked me if a name really needs to have a meaning, giving it little thought I said no. This however, did lead me to a few more questions though, why do we give these names to things? How did we decide upon these names? Sadly, I don't think there is a answer to these questions, though I still wonder.
On a different note, I've noticed something that I find very odd. Myself and Yasi are the exact same heigth. Maybe it's mere coincidence ... After all, what else could it be? I found myself wondering ... And then I decided to find some other things out. We went into my, what I call my house, and I took my sandals off, and asked her to do the same.
She did as she was asked with barely a word. "Yasi, could you walk around here a bit?" She tilted her head a bit, but did as I asked. After that I put my own foot on top of each foot print, one at a time, none of the foot prints changed a bit. I then took my gloves off, setting them by my sandals, and then asked her to put hands her hand out, I then put mine up to her's. They were exactly the same shape and size, "Yasi, can you show me your hands?"
The wheels in her head were turning faster and faster as she again, did as I asked. I showed mine, down to everything detail they were the same. It was all so vexing, I felt hesitant in calling it all a coincidence, finally Yasi had, had enough, "Okay, Mivii, what's going on? You've been asking me to do these weird things, and then you copy me? Are you trying to make fun of me or something?"
I shook my head, "Of course not ... I just wanted to know some things, that's all"
She put her hands behind her back and leaned towards me, "What kinds of things?"
What should I tell her? That I seem to somehow have most of her same features? "Umm ..." I couldn't find anything good to say, and I didn't want to say anything weird.
She leaned away, and sighed, "Mivii, we're friends. If there's anything you want to tell or ask me, you can. You know that, right?"
"Anything?"
She nodded, "Anything at all"
I swallowed my breath, and decided to put my faith in my friend, "Okay, this is going to sound ... Really weird"
"Okaaay?"
"For a while I've noticed that the two of us are of the heigth ... And at first I thought it was just a coincidence ... But after asking you to do all of that ... And then ... Finding out that everything matched ... I've started to wonder if there's a reason"
Yasi closed her eyes, "That seems to be all you really do, wondering about ... If there's a reason for why I gave you your name ... Or what it means ... ... ... But ... Maybe this time there is a reason. The day we first met ... I all of a sudden began to feel weird ... Like I had no control over what I was doing ... And then I saw you thinking ... and I felt as if I knew you"
My eyes widened, "You ... Felt ... Like you knew me???"
"Yeah"
"I felt the same way, whenever I looked at you. I was trying to decide how I would meet with you, when you came up to me all on your own"
"Well that's weird ... Tell me ... Did something happen, after I left?"
My vessel stiffened, "N-no" I lied.
She opened her eyes, "Don't lie. The next time I saw you, you acted like I was going to do something bad to you. I'm not going to do anything, so just tell me what happened"
"... ... ... Please promise me we can still be friends after"
She shook her head, "I really don't know why you're acting this way. But okay, I promise we'll still be friends after you tell me"
I shut my eyes, put my hands on my hood, and slowly pulled it down, "This is why"
"... ... ... Mivii?"
" ... Yes?"
"I really don't get what you showing your face to me has to do with what happened?"
"Y-you don't? Shouldn't you be ... Scared?"
"What? At seeing what I do whenever I look in a mirror?"
"What?"
She grabbed my arm left arm and slowly tugged, "Come with me" I obediently walked with her to the waterfall. We looked at our reflections, I was speechless. We looked the same ... Aside for my eyes being the same amber and her's being baby-blue. Somehow, my face had changed, but when? That was what I wanted to know.