Personalized Dinosaur 3rd Birthday T-Shirt. The colorful and fun design includes polka dots, stars, jungle leaves, and other nature elements, making it a cute and playful choice for a birthday celebration. Whether you're looking for a gift or outfit for the birthday boy or girl, our dinosaur 3rd birthday collection is sure to delight. 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.