Maybe you wear glasses. Maybe you have a lot of freckles. Maybe your hair is a different color. Maybe you travel the world on four wheels. Maybe your skin is a different color. Maybe everyone can see your surgery scar. Maybe you use hearing aids to hear the world better. Maybe you're not the first one picked for team sports.
There will always be people in the world that look at or treat you differently because they think you look or act differently. Just like River, you can do whatever you put your mind to. The only person in the world that can keep you from your dreams is yourself.
Believe in yourself.