Samandriel
I started dreaming just a few weeks before my ninth birthday. Which was about two months ago. Then one night, when I was helping strike the set after my big, end-of-the-year dance recital, I pushed one of my younger classmates out of the way of a falling piece of equipment, and manifested a bright blue, chitinous, arachnid exoskeleton, which protected me while I shielded my friend. The next morning, when I woke up, I had metamorphosed into the same physical age as I am in my dreams. Sixteen instead of eight.
I also have faster reflexes, and stuff, but it's the blue symbiote that comes out when I'm nervous or scared that's the freaky part. That and sometimes I worry people will think I'm mentally challenged, because my mind is half the age of my body. I'm just borrowing memories from the dreams and trying to fake it till I make it.