Personalized Don't Push Toddler T-Shirt. Nuclear Engineer, Don't push my buttons in a radiant yellow oval is a humorous design for nuclear engineers. Fun gifts for birthdays, holidays and graduation. 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.