Personalized Baseball 8th Birthday Long Sleeve T-Shirt. Baseball 8th birthday boy. Baseball league style with bats and varsity letters. Sports theme for your 8-year-old's b-day party. Happy Birthday eight-year-old! Pre-shrunk 100% cotton 6.1 ounce long sleeve t-shirt. Double-needle stitched neckline and sleeves. Quarter turned. Shoulder-to-shoulder taping. Adult: S, M, L, XL, 2XL, 3XL