Personalized 3rd Birthday Monkey T-Shirt. he happy birthday monkey motif is a cheerful way to commemorate this special milestone in your child's life. Let your little wild one stand out with our unique and cute birthday accessories. Wardrobe essential for looking good, 24/7. 5.0 oz., pre-shrunk 100% cotton. Seamless 1x1 rib collar. Shoulder-to-shoulder taping. Double-needle stitched sleeves, bottom hem and front neck. Note: greys are a cotton/polyester blend.