Personalized I'm A Big Bro Octopus Cute Brother T-Shirt. I'm A Big Bro T-Shirt - White has green and blue chevron striped octopus pair for a little boy with a new sibling. 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.