Personalized Believe in Yourself Youth Long Sleeve T-Shirt. If you believe in yourself, you can achieve whatever you set your mind to. Believe in Yourself Youth Long Sleeve T-Shirt - White, featuring the brave and confident "Cordelia" from the children's book by Michelle Nelson-Schmidt. youth long sleeve t-shirt. Shoulder-to-shoulder taping. Youth: S(6/8), M(10/12), L(14/16), XL(18/20)