Personalized Little Monkey 6th Birthday Boy Youth T-Shirt. THIS LITTLE MONKEY IS SIX 6th birthday Youth T-Shirt - Heather with a cute smiling boy monkey holding a banana. 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.