Personalized I'm Going to be a the Big Sister T-Shirt. Celebrate the arrival of a new sister with our charming elephant-themed apparel and gifts. From baby sprinkle ideas to sibling brother or sister gifts, our collection has everything you need to make the big sister feel special and loved. 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.