My now eight year old stepdaughter received a TBI and severe lung injuries among many other serious injuries in a car crash when she was six. She was unconscious in ICU for three weeks. The doctors begged us to pull the plug on five different occasions and told us she would be a just above a vegetative state if she ever woke up. We refused and a year and a half later she is transitioning out of special ed into regular classes and is walking (despite partial paralysis) on her own, talks completely normal, and is enjoying being a kid.
It's amazing how resilient children are and you should never count them out until all is said and done. It makes me very happy to see stories like your god daughters.
In my experience, you should have a little more faith in the doctors than they have in themselves. They like to paint the worst possible picture, to cover themselves in case things don't go well.
God bless her and I'll keep praying for a speedy recovery!