Personalized 1st Cinco De Mayo Fiesta Sombrero Youth Long Sleeve T-Shirt. It's my 1st Cinco De Mayo Youth Long Sleeve T-Shirt - Royal Blue May 5 holiday celebration fiesta sombrero logo baby's celebration gift. youth long sleeve t-shirt. Shoulder-to-shoulder taping. Youth: S(6/8), M(10/12), L(14/16), XL(18/20)