Personalized Purple Dinosaur 3rd Birthday Youth T-Shirt. LIL' THREE-OSAURUS 3rd birthday Youth T-Shirt - Black with cute purple cartoon dinosaur and big polka dotted number 3. Let the good times roll in a durable T-Shirt that takes kids from school to play in an amazing array of colors. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar.