You are a stud among all dads. There is nothing more precious than the gift of time and you're so generous by providing your daughter the highest quality time available. I admire your dedication and resolve.
Many years ago I worked in the Cardiac Surgery unit at St. Louis Childrens' Hospital. I learned first hand the reseliency and power of children and their ability to heal. Kids that came to us listless, dusky, and lacking any energy received therapies that within days allowed them to be playing normally and within weeks required a few time-outs. You are in a well-renowned facility that will provide the multi-disciplinary team approach that will offer the best results for your treasure.
You are doing the right things and more... keep up the good work and trust that we are all behind you and Lexie.