Personalized Race Car 4th Birthday Toddler T-Shirt. Cute Race Car with the number 4 on it for your little boy's 4th Birthday is fun and colorful and comes on a party Toddler T-Shirt - White gift. art c. Ne' Metzger 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.