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. Everyone loves our Custom T-Shirts! 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.