Personalized Superhero 2nd Birthday Toddler T-Shirt. Happy 2nd birthday! Celebrate your baby's second b-day with this cute I'm 2 super hero design. Happy Birthday two-year-old! A toddler-soft cotton tee in look-at-me, big kid colors. 4.5 oz., 100% combed ringspun cotton. White is sewn with 100% cotton thread. Topstitched rib crew neck. Double-needle stitched sleeves and bottom hem. Shoulder-to-shoulder taping.