Personalized I'm One Superhero Girl T-Shirt. I'm One! Superhero toddler girl in a pink cape, hair bow, and diaper is ready to fight crime and nap time. Cute gift for any superhero one year old's 1st birthday. Everyone loves our Custom T-Shirts! Wardrobe essential for looking good, 24/7. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar. Shoulder-to-shoulder taping. Double-needle stitched sleeves, bottom hem and front neck. Note: greys are a cotton/polyester blend.