Personalized Pregnancy Announcement I Am Going to be a Big Sister T-Shirt. Embrace the sweetness of family growth with a touch of humor, and let everyone know that sprinkles are essential, especially when welcoming a new baby. Make your announcement memorable with this charming and fun apparel. 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.