Personalized 6th Birthday Football Sports Boys Youth T-Shirt. 6th Birthday Youth T-Shirt - Pacific Blue has big football sports ball with number 6 and being six is a ball slogan for boys who love football. 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.