Personalized Unicorn Birthday Train Youth T-Shirt. A cute rainbow colored unicorn rides a steam train and lets the world know It's My Birthday! Cute gift for anyone who loves unicorns and trains. 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.