Personalized 3rd Birthday Puppy Blue T-Shirt. I'm three! A cute blue puppy has a birthday hat and a cupcake with a three shaped candle. 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.