Personalized My first St Patrick's Day Baby's First St Patricks T-Shirt. Whether you're dressing them up for a photo op or just want to add a touch of luck to their wardrobe, this outfit is a must-have. Get ready to create lasting memories and celebrate your baby's first St. Patrick's Day in style! 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.