Personalized Super T-Rex 3rd Birthday Youth T-Shirt. Rawr! A T-Rex superhero wearing a birthday hat is surrounded by a colorful burst of confetti. Cool 3rd birthday gift for your three year old. 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.