Personalized 1st Birthday Unicorn Kitty Long Sleeve T-Shirt. Adorable rainbow unicorn kitty celebrates your baby's 1st birthday. I'm One! Cute first birthday gift for your one 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