Personalized Little Elf 3rd Birthday Youth T-Shirt. Youth T-Shirt - White for a little elf's 3rd birthday with a polka dotted number 3 and snowy striped North Pole sign. Perfect for Santa's helper on his or her Christmas birthday. 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.