Personalized This will be the Best Birthday Ever Long Sleeve T-Shirt. While all birthdays are worth celebrating, this one will be the best ever! This will be the Best Birthday Ever Long Sleeve T-Shirt - Kelly Green, featuring Mouse from the children's book "Dog and Mouse" my Michelle Nelson-Schmidt. 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