Personalized Superhero 6th Birthday Pink Women's V-Neck T-Shirt. Happy 6th birthday! Celebrate your child's sixth b-day with a cool SUPER 6 superhero party. Happy Birthday six-year-old! 5.0 oz., 100% pre-shrunk cotton Athletic Heather is 90/10 cotton/polyester 1x1 rib collar with mitered v-neck Shoulder-to-shoulder taping Ladies' fit