Personalized My 1st Marathon Fitness Running Toddler T-Shirt. My 1st marathon Toddler T-Shirt - Charcoal has cute fitness themed running design that makes a great souvenir. 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.