Personalized Cordelia and Birds Believe in Yourself Youth T-Shirt. If you believe in yourself, you can achieve whatever you set your mind to. Cordelia and Birds Believe in Yourself Youth T-Shirt - Heather, from the children's book "Cordelia" by Michelle Nelson-Schmidt. Let the good times roll in a durable T-Shirt that takes kids from school to play in an amazing array of colors. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar.