Baby Brother

I'm working on a children's book and this is the first image I've created for it. 

I'm deriving the book from my own experience; my little brother was born at 6 months and although he's an adult now he didn't have an easy childhood. I certainly didn't help being the only healthy child, I was always too rough with him. The book I'm working on is about a child who's baby brother is born premature. Even though he's tiny and frail, the child makes light of the situation because any brother is better than no brother. I keep referring to the main character as "the child" because I would like to give her/him an androgynous name so all children can relate. 

This is one of my first full painting on Manga Studio 5. Any tips/suggestions are welcome!