Personalized 1st Birthday Cupcake Pink T-Shirt. The little girls 1st birthday t-shirt is a sweet and stylish way to celebrate your one year old's special day. With its pink and red color scheme, it's the perfect outfit for the birthday girl to wear on her big day. 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.